Which Openings Should I play to increase my Rapid Rating?

I think you're asking the wrong question if you want to improve your rating. You should probably spend less time thinking about openings and more time on reanalyzing games, improve your tactical ability by doing puzzles, etc...

Yeah, I don't think openings is where you should be looking...

@VEDANT_KUBADE
Any opening should work because there is no superior opening which guarantees a win.
Which openings do you play?
~ One should play openings they are comfortable with.
If you don't have any problem with the opening you play, stick to it.
You need to learn the theory about the opening you prefer. You can look for improvements by watching videos.