Participating in major CODM competitions

I'm quite new in this game (like almost 3 months into this game) so my experience won't be very high, but my in-game level is quite high (Lvl. 144) , my current rank is Master II for MP and BR, good in using Assault rifle and SMG's, still improving on sniping skills and and using shotguns. Would be nice if you could guide me in COD in terms of playing style, strats and many more since I'm quite new to the game. Preferred language is English. In-game username is Aszue_SvG