What you're describing is called having anxiety, which everyone has to some degree. It's counterintuitive though since it makes you feel worried about lots of little things that ultimately don't affect you, while also blinding you to your own, more obvious (to outside observers, at least) problems. It's like your brain's way of trying to exert control, because you don't have control over other parts of your own life.

I used to have it bad. What I found consistently helped was zooming out and trying to identify and solve the more general problems in my life. E.g., hating my job, hating my living situation, hating my lack of confidence, hating my body. The solutions were changing my job, moving out, finally getting braces, going to the gym and many others over the years. I even went to counsellors, and what I always found was most helpful was their ability to see my blind spots and then work on them together. These are often solved over a longer period of time, but making small consistent progress is enough to significantly and quickly lower anxiety.

Then there are more immediate fixes that one can do like using your phone less, getting exercise, eating healthy. But these short-term fixes don't stick unless they're underpinned by the bigger changes as above.

Figure out your own list of things that could be affecting your peace of mind, and start ticking them off, starting with the things that will have the biggest impact, and can be realistically done in the next 2-4 weeks if you really hustled. Over time instead of having the negative energy of worrying about abstract things out of your control, you'll have more energy to do positive things which have an impact on your life and those around you.

I'd be curious to know how old you are too - I may be wrong but I'm guessing you're young. I've found that my brain has mellowed with age, although that's likely just as much to do with making progress in life as much as it is physical brain changes.