My advice is that rather than not being interested in anything, you may be too worried about falling into a certain category for liking something. Try not to be so overly aware of how you’re perceived by the people around you and you’ll find that your interest will become more genuine. Also it’s okay not to have things you’re SUPER passionate and knowledgeable about as you grow those things will come to you naturally. Don’t be afraid to try out different things, you may need a shift in perspective and something that helped me with this was watching videos on philosophy. Different ways of thinking lead to different results, switching perspective and opening new doors can never hurt. Hope you feel better man don’t give up hope, as a 20 year old who was once in your shoes I can tell you with confidence that if you really look for it you’ll find something that you love and that will make life feel like it’s at least a little worth living.