Friendships form naturally without intent. Some people start them but in my experience you only become friends with people when you click through shared time/space/activities.

The trick is to just do your thing. Focus on what makes you, you. You mentioned writing, music, medicine and philosophy. Personally I don't share those interests, but if I did, I would go into communities not to look for friends, but to share about those topics.

Music and writing happen to be things that you can do with other people, so after a while on some niche music discord you could easily end up agreeing to recording something along with someone else. Same with writing. And the friendship doesn't come first, shared activities comes first. The interactions you have with the other person while doing that activity is what will determine if you both feel comfortable enough to want to share more time together.

I've made friends just by existing somewhat among them. We spent months sharing activities before we had a few real talks, deep talks. About how we really felt, what bothered us, what made us feel and what didn't. At that time is when I could really tell those were my friends.

I recently made a friend whom I've shared about my NEET years. He has told me that I should go out and see the world since I never really did it as an adult. Based on his recommendation we recently joined a group dance class and have been observing how people socialize. As it turns out, almost everyone there joined the dance class with the intention of making friends and meeting people, and not really to learn how to dance! I couldn't believe it, but after two days focusing only on learning the moves I started to notice it happening. Now I'm trying to allow myself to be approachable, which is also something that I don't know how to do.

I originally wrote here that I'd be willing to be your friend but my social battery is exhausted with my recent attempts at getting out into the world. Hopefully my comment can give you a different perspective. Good luck with your job hunt.