CSGO Rank

I would say, having 5k hours in my back, that, you have to forgot about ranks etc, just practice a lot. I've done for a few months daily 5-6 hours AIM practices (aim_botz map, or aim maps), and can say it helps a lot. Also you need after you've got a decent aim and crosshair placement, to play a lot. I mean you need to learn about positioning, have map knowledge on every played maps, and just grind matchmakings. If you reach by yourself around LE-LEM, I can say stop playing MM's because it is pretty cancer and move to a better platform, if you can afford I can recommend ESEA, if you cant just play Faceit, but be careful, dont except too much from these, lots of kids playing it and they're crying if they lose etc, its still the same game.
Also 128tick compared to 64 much more better, you'll notice if you start to prefire a lot etc..
If you want to ask more feel free, although I'm not playing the game anymore, I've got a lot of experiences over the years.