Lately I made some comments in a blog which is like "I think I should start to write stories after I completely ...... “ and someone pointed out that it should have been written like " I think I should start writing stories after I completely ... " it actually makes sense, But I just wonder is "start to write" grammatically wrong in the above context?
It means the same thing. Anyone who says differently is a pedant. You could say it both ways and it will mean the same thing; in fact, I think yours is probably more proper because using the infinitive there makes it sound as though it were going to happen in the near future, whereas using the gerund form intimates that you may be starting right after you get done typing out that sentence; however, it doesn't have to mean that; I'm just pointing out that the difference may be so subtle that it doesn't even exist.
I hope that might have helped. Take care and Godspeed.