Hi guys! As you can read in title I´m starting to play PvP and I would be nice if you recommend me classes, professions in PvE to improve weapons and armours to be better in PvP mode,… Those things.
Thanks for your support! 
Best class PvP?
I dont know you prefer pvp or WvW or roaming but mesmer is a good choice and for more detail information you need to visit mesmer forum.
Each person will give you different opinions on which class you should pick. If you’re into tPvP then I’d suggest you to look at mistpedia to see top winning team comps. As far as I know for now every class is too op now and needs nerf.
From my experience I’d suggest you to speak with people in game, because forum is full of biased opinions. Warrior will always have it’s place in every team and they’re good in duels. Guardian is also a good choice (bunker guardian is in like 95% teams), but in 1vs1 situations you may have problems as guard is slow, like really, really slow. Necro is great, not so hard to handle, needed in teams (+ fear in wvw is one of the most enjoyable things I’ve ever met). Engi is said to be op, but it has very poor access to stability and condi removal. Mesmer is good due to his utilities.. Well.. no matter which class you will pick you might be good with it. The most important thing is you have to enjoy your class and work on it, one week is not enough to be good. I also want to add that it is a good idea to try each class. You don’t have to main and master each, but try them so you can learn how to counter certain builds.