People keep saying “looks nice” but I want to be more specific in that different people think different clothes look nice. Some think business casual should be standard unless you are a laborer and prefer those. Some prefer very casual t-shirts and jeans, or sometimes jeans of a specific style, usually as long as they are clean and not stained. There are a ton of different styles you can choose from. I would suggest that overall most people prefer no stains and smelling nice (very light cologne, or even just scented laundry soap), and clothes that are not too big or too small. The area where you live probably has specific taste/style, and you can look at others wear to determine what you think will work for you. You can also try on a bunch of styles and see what feels good and what you think looks good on your body specifically.

I also want to say that, regardless of how you look, try and be a well rounded person. Look for a social group that you enjoy being in, stay in shape, learn to care for yourself and others (like cooking and cleaning, this can go a long way in attractiveness). Although some relationships start by one person they can help the other, either with money or emotional support, those are not often stable nor healthy relationships. If you are in a healthy place by yourself, you can develope better relationships.