I don't have any female friends 

From a woman's perspective, a lot of my single guy friends who have trouble interacting with girls is due to the fact that they misinterpret a girl's actions. Yes, a girl may talk with you (just to be nice and courteous), but it doesn't mean they have interest in you romantically. I can't tell you how many guy friends have asked me if a girl is interested in them. After they tell me all the details, I give them my thoughts and opinions, they ignore my thoughts and opinions and the majority of the time I'm right. The girl was NOT interested in them, but the girl just couldn't verbally say no that they are not interested so they'll end up either making up excuses, ghosting, or making small talk and then eventually just stop responding. From watching your video, I like your positive personality and your willingness learn and grow from that interaction is honestly refreshing and awesome.

Girl here, I understand some girls can be wary of guys but trust me some girls just won’t add anyone willy nilly. I’ve been rejected by plenty of girls when I try to be friends with them. Some of them just want external validation and attention (platonic or otherwise), some maybe elitist, some girls just don’t vibe. It’s not on you really. Having been in a girls’ school for 12 years, some girls are just childish even into adulthood. My experience is, find a part time job or a hobby where there are a good mix of genders and just have fun with conversations and initiate fun activities together. I used to have trouble talking to guys because of my upbringing but after working in an environment where there’s an equal amount of people of all genders, I learnt to talk more and express myself freely. Go for events and talks and just meet people, maybe befriend your guy friends’ girlfriends/wives and hang out with them in groups. You’ll learn a lot that way too. I only started opening up to platonic male friends after befriending my girlfriends’ husbands and boyfriends. I’ve had very terrible experiences trying to make friends with guys who only want to get into my pants

disclaimer: i'm a woman, not a young girl but lemme share with you my thoughts. you mentioned attended some event and there's this girl who sa sat next to you whom you had a nice exchange with but you added her on ig and she didn't seem to respond. my question is, why did you need to add her? if i were her, i'd think you're probably way too fast or i might assume already that you're interested in me as a girl. she probably thought that way or she has a boyfriend and she forgot the time she talked to you. as to you wanting to connect with girls, you can do that but if i were to give you an advise: be natural. talk naturally and talk to them equally how you'd talk another guy. next, don't treat or act as if it's your goal to connect with girls bec girls can feel this through their instincts, so just be natural, not overfriendly, just authenticity-that's it. another point, do you know the phrase "don't chase; attract"? apply that to yourself. don't chase and be natural and girls will eventually gravitate towards you. also, whenever you talk to a girl, imagine talking to your little or older sister. that's all