Hey Teo,
Welcome to GMATClub!
For Quant Preparation, these are few of the links on GMATClub which I think will be beneficial.
1.
Quantitative MegaThread2.
Q44 -> Q50I would recommend you to go through the Ultimate GMAT Quantitative Megathread
in order to build your concepts and use the knowledge you have gained on questions
that you are finding problems with. Additionally, you could follow Bunuel at our
Quant forum. Do all the questions on his signature. If you were to ask me, you should
try and solve at least 34-35 questions with reasonable accuracy and that should help
increase your score to atleast Q49.
Hope this helps you!