Mjen723126: As I understand it, the “XP” will make you a better WGT golfer, correct???
I'm afraid to say: Nope.
XP stands for eXPerience - it shouts out "due diligence" and "industry".
At the lowest level, you get 1 XP for each shot you take. There are extras for awards (in stroke play), and for game completion (in any game).
From a vantage POV, it says, you take on the grind, and you are awarded with growing levels which allow you to spend some hard-owned credits on items like equipment and and other items to - hopefully - better your game.
To become a better WGT golfer, you'd have to increase your skills, and increase your equipment quality (which comes down to the right choices at higher levels, after committing to some XPs, and some more).