People have a lot of negative things to say about Grammarly but there is a free version. It won't catch all of the mistakes but it will catch a lot of them. The more your writing improves the more readers you will not only attract but keep.

No one is going to follow a writer who publishes with a ton of errors in the work. It's too distracting to try to figure out what the intent of the post is instead of simply being able to read it and enjoy it.