So what you need to get out of silver? My experience from starting to boost my cousin out of it (he is now at LE) and having to play against these headaches:
-dont trust anyone. your teammate wont get that kill, he wont cover you, he wont throw flash for you, his smoke is shit.
-read the enemy team. most of them going for the same route every round (they have max 2 routes).
-know which enemy player plays which site on the map in CT (so if any of them is really trash you can push that site every round. or if somehow anyone plays good you can avoid until post-plant)
-be a baiter. let your trash teammates go in first as Ts and trade them.
-get a right mindset. if you start the game with the mindset of "ah, they are trash this game is gonna be so easy" and they kill you like 3 times in a row your confidence is non-existing anymore and you will be raging and malding.
-dont follow your teammates with economy. they mostly force up every damn round. save for your prefered gun which you are good with that day. (sometimes i'm utter shit with rifles, but im like a god with awp. sometimes its the other way around)
-as a CT try to go to the site they attack more often or be on a position from you can easily rotate or push behind enemy lines.
-there is a looking to play menu (if it is still there, i didnt use it since last operation) and try to get into lobbies. add the players which were good enough and try to play with them until you get out)
I also play on a shit laptop, 60 Hz, 50-100fps (if they throw molotovs and smokes then i just give up, then i have non-existing fps :D) I'm at LEM, but i only play with my cousin (the one i boosted from silver) and a max of 5 maps / 1-2weeks. GL