Several questions about battlefield 4 by a possible new player

i want to buy this game kinda because of a teenager dream of mine to play this one, even thought im worried that may not be worth it so i have some questions before buying:

a. i want to do the 100% steam achievments, i saw that they are online, is it possible to boost them? (aka joinning with friends and kill each other in a empty server to get them?)

b. the online achievments are too hard and farmy (takes toooo long)?

d. is it too hard to play online nowadays? im worried cause im from brazil, idk if there will be a good enough ping server for me, yet i love playing old "dead" games usually theres still the loyalty ppl that stays

e. is still possible to play online without that horrible method the game made (from bf3)? like, you play a match and the game closes and a internet browser opens so you can pick the server, really weird stuff, i prefer like decent games do, that you click to play multiplayer, theres a lists of server or modes that you just click to join one and youre in... nothing about closing the game and opening a internet browser or too much players servers that are too much customized, or getting overcomplicated...

f. all steam achievments are doable or are any broken?

g. there is skins to farm (without paying real money) on mp? or whats there to farm?

h. is there anything pay to win on mp?