I use Grammarly's online text checker. It is checking this answer as I type and flags many, but not all, obvious typos and grammatical mismatches, etc.
It's good for that, but I still reject many of those suggestions.
My experience as a native speaker with other, but similar, grammar checkers is they are a serious waste of time and energy. They flag far too many "errors" that are correct - often a style choice or idiomatic use I specifically wanted.
Note that most of Grammarly's paying customers are businesses. It is designed to suit their needs, not the needs of ordinary folk wanting to improve their communications skills. It is a useful tool for businesses wanting to check their technical documents. I wish more IT businesses would use it to check their so-called User Manuals.
The point I would make for someone learning English is any benefits of using their detailed reports will fade over time - if you are using it wisely.
You should never just accept its suggestions. Instead, look into the reasons behind them. That should help you identify some of the finer points of grammar you should be trying to learn.
Most of all, do not apply its suggestions unless you understand why they were made and you agree they are appropriate in this instance. Hopefully, after not very long, the free online checker will then be you all you really need.