Helping with the analysis

So I played black here, and I played in this position Rc8. My ldea was to kick his queen and gain control on the open c file, however according to the engine it says its inaccurate move and I should've played g4 instead. Can someone help me with the logic behind g4 pawn push and what does it accomplish?

And also how do I post the whole game here?

g4 sets the pawn majority in motion and comes with the threat of Qh4+ and g3. The threat itself is easily dealt with, but that gives Black time to march his pawns down the board.

Oh ok I get it, thanks buddy. So Rc8 is inaccuracy becuase now he can move his queen to e2 and then if I play g4 he can meet the check with Qf2 so I wont be able to check and play g3 with a tempo?  

...g4 is the fastest win. Of course, ...Rc8 also wins so it isn't a terrible inaccuracy, but your queen needs some air and ...g4 provides it to great effect. Your queen and g pawn become very powerful and white will lose very quickly.

Thanks for comments they were really helpful!