How can I be more dominant? Not even when it comes to girls (altho yes it's a part) but just in life in general

For background story, I was a super nerdy overweight guy for most of my teenage years, so I never really got a chance to develop social skills or assertiveness. I lost 50 pounds freshman year of college, felt a lot better, hooked up with some girls, but was still a welcome mat with no spine. Turned 21, gained 20 pounds, and now seeing how painful it is, not being assertive. Many people (especially other guys or 8/9 girls) don't give me respect and just ignore me. I don't even think it's sexual, cause guys ignore me all the time too and speak over me like if I wasnt even there. Most of my friends are girls actually. I think part of the problem is that I come off as needy or maybe too energetic

I just wanna know if there is a way to make myself less nerdy and more assertive. Im already taking some steps towards it, I notice when I nofap I become a lot angrier, so at least that makes me more assertive. I also started lifting weights again, to get to the form I had sophomore and junior years. I dont have many hobbies or interests aside from the internet, but I do like cooking and painting and I know three languages, and I hope to learn Portuguese next to make it 4!

But even so, I don't know how I can be more assertive and stand up for myself. Or how to have any type of social value? Do you guys have any advice? I'm ENFP on the MBTI scale, if that helps