I'm experiencing severe hair loss. ㅠ

I used to have a lot of hair and strong hair roots, and my hair was really thick.

In my twenties, I didn't eat well or even starved myself, and I couldn't eat nutritiously, mostly sticking to a single food diet.

I've lost weight from eating, but I'm also losing a lot of hair and my hair density has decreased, so when I tie my hair, it looks thin and unappealing ㅠ

I feel like my health is getting worse again, so I started taking good care of myself again, but the lost hair won't come back, you know.ㅠ

Please share if anyone knows how to reduce hair loss, strengthen hair roots, or thicken hair.ㅠ