Welcome Elyas,
The more questions you can study, the better. Try not to rush, the PPL is just a step along your path to becoming a confident pilot. You are better to take your time, and pass your ground school exams with ease and confidence, than to "cram" information just to pass, and then forget it.
Remember that you will receive ground school training only once, and probably not again, until you seek a higher license, where the actual flying skills, you will practice every time you fly in the future. So get the ground school topics really well into your mind, because they do have to last in your mind for your whole career as a PPL - they are not so easily refreshed!
Search topics here, and you will find all kinds of wisdom. But the reference books are the "official" source of information....
All PPLs have done it, you can too!