How can i speak English well?

-> How can I speak Englsih well?

 I think studying English constantly is very difficult.

-> I think to study English constantly is very difficult.

Isn't there a shortcut for studying english?

-> Is there an easy way in studying English?

Isn't there someone to show me the best way for studying english?

-> Is there someone who can show me the best way in studying english?

I am always interested in improving english. Always take care of oneself!

-> I've been always interested in improving my englsih skills.  And take care of oneself!