I can't type, is there a limit for free user?

I can’t type anything. What’s the problem?
I’m using laptop and chrome, google sync account.

There is no limit except uploading files afaik. Did you my any chance hit the lock icon?

Yeah, what @Subhinay suggested is the most likely issue. You might have resized the app and accidentally clicked on the lock icon. Resize it to really narrow again and you can check if the lock icon is active (it will appears blue if it’s activated).