Name: Kristofer
Age: 18
Gender: Male
Height: 5'6
Ethnicity: Caucasian
Build: Slim
Hair: Black /short
Eyes: Brown

I'm an introvert, I over analyze, think I have to plan every line of conversation with someone new out.
I've never been able initiate anything and I have terrible approach anxiety. I feel every girl I've ever gotten interested in me, was a result of A: my interests, or B: her making all the moves.
I go to several concerts a month, always by myself, and I feel like every girl that I'm interested in approaching is 1) insanely beautiful a 10 to me. or 2) is preoccupied with whatever they're there for, or who they're there with, and would only be annoyed if I talked to them.
actually I feel that way all the time, that If I stop a girl somewhere and start talking to her, that I'd only be annoying her.

I can't think of anything to say past an opener, because I'm shy, don't know where to take the conversation from there, and how to get a number of someone that DOES interest me. I want to be able to build attraction, and not get "friend zoned" by every female interaction I have the balls enough to make.

So, offhand I can think of two occasions in the last year, I was able to talk to someone I found attractive.

The first one,

I was at a small show at a cafe in a nearby town to me,
I was there for a proper reason, and ordered my food and drink, and was watching the performers.
About halfway through my meal 2 beautiful girls, aswell as one guy looked like he could have been one of their boyfriend. I didn't pay much notice to them, but after the show was over, and I was leaving I noticed the guy had left.
I very awkwardly backtracked to my table (because I had forgotten my take home bag) and very awkwardly looked one of them and said "I don't mean to bother, you.. but I had to say I think you're very beautiful" I was aware even in the moment I came off as a creep, but It was honest, and a step in the right direction. although it took ever fiber of my being, and throwing myself over the metaphorical edge I was extremely bashful, and wasn't comfortable with the situation AT ALL.

The other one happened in January at a black veil brides concert I was at.

I was in the floorspace enjoying the show with my brother, and right next to me, I look over and about an 8/10 is enjoying the show next to me, dancing, and singing along with her friends. she was there with about 4, but I only saw her standing next to 1 and the show was well underway.
I couldn't help but look at her after every song or so and check her out I guess.
a time or two I caught her looking back at me and smile. I was building up courage to talk to her (which i now know is a mistake) and thinking of the right wording for what I was about to say.

Finally I tapped her on the shoulder, and whispered in her ear a lot more confidently with this one,
"I had to tell you, I think you're really cute."
she responded with "Thanks, you're not so bad yourself"
I didn't know where to take it from there, and the band was just ending, so I walked away.
I went to merch (cause that's what I do at a show, and it was a small venue)
she had to walk past me in line for merch to get out of the venue, and I saw her again leaving.
we made eye contact and again she smiled and got bashful and blushing.. she came up to me and asked for my number. since we've talked, I've built attraction and it's all good, But its all been through text, and I found out after that she lives about a 4-6 hour drive from me.

It seems all my game is flukey..
I don't know what to try, I've been watching "the pick up artist" and "keys to the VIP" and watched interviews with Cajun especially. But I don't know if much of it is sticking, I sure as hell don't know how to build attraction, and after an opener I have nothing to say.
Can any of you spare some words of wisdom

for a youth with no game?

yeah it seems my biggest problem isn't opening (i don't really care how I open)
but transitioning to something to say after that.
after they respond to the opener, I don't know what's natural conversation.
I'm an introvert and don't talk alot to my friends even much besides directly answering them.

EXAMPLE

I'm walking through town and I see a really attractive looking girl.
I could walk up to her and say, Hey, I was walking and couldn't help but notice, you and I had to come over here and introduce myself. Hi I'm ________

But after that what can I say?
do I address the situation ? just walking outside and being in town?
or do I ask her something I'm curious about.
like what kind of music are you into?
what bands do you like?

I honestly have no idea whats a natural approach to take..

I think the idea is to generally try not to ask any questions within the first 30 seconds or even the first minute if you can make it possible, try making assumptions about her have abit of fun in the guesswork.
For example this is what Yad would possibly do and ive personally tried it myself and it kicks off the conversation well.

" Hi excuse me can I just say something really quickly' I just saw you from over there and I just had to come over and say that you look really nice today "
Her: "Oh thank you " ( now before she starts to move again you will need a follow up )
You: " Yeah I like your cardigan it matches your slim jeans so well and kinda brings off a positive bubbly feel"
Her: " Oh really' yes I am just wearing because its really quite a cold day out there today but thanks yeah " This is where you can introduce the first question, remember asking too many questions too early gives off that sorta neediness slamming her with too many questions. Think about it if someone random from the street guy/girl approached you and started asking straight away " where do you live? " " what do you do?" , you would get very suspicious and possibly just walk away from them.
You: "You look like you could be English or part Italian yes? "
And generally from there she might talk about where shes from and what parts she does have per say she might have some Irish blood in her etc, so from then on you should relax into the conversation.

That's just my take anyway I don't word it like that all the time I am trying new and different ways all the time.