The reasons why they can’t stay with their parents are that the parents don’t give them a good education, and sometimes becausthe parents hit their children.

Need to put an article ("a") before good education. Adding "them" also adds more clarity and fluency.
There is no need to add "because" since you are already stating reasons.
Add the article "the" before parents in the last part.

I am trying to provide a good education and improve their abilities by helping them with schoolwork orand offering advice.

You tend to miss your article "a" again.
Also, using "or" isn't necessarily bad, but by using "and," you are offering both school work and advice. Using "or" just doesn't go well as you are providing both those things and not just one.

When I’m not at work, I enjoy spending time at the gym to relax and improve my English.

Do you enjoy improving your English at the gym? The gym is usually a place for physical exercise. My Grammarly App is telling me you wrote this correctly, but the app can be wrong sometimes, so I don't know. I would have preferred either adding a place before "improve my English" like "at my home to..." or making "improve" a continuous verb.

Before, I didn’t care about my English level.

This is a dependent sentence. A dependent sentence can't stand by itself.

To conclude, to improve my daily routine, what I want the most is to sleep more, as I don’t really enjoy sleeping and often feel exhausted.

The article "the" is missing.