Young people enter a university as they want to build a friendship with influential people in order to have a valuable assistance ("val. assis." sounds well?) in the (or without “the”?) future.
"Young people enter university wanting to make connections and network with influential people in order to potentially gain valuable assistance in the future."
Note: "Valuable assistance" does sound okay, but I could even say "to have a valuable/useful/priceless asset."
They also want to learn a profession and have an idea of who they will work in the future.
"They also want to learn a profession and have an idea of who they will work (for) in the future".
Note: Just need the preposition of who they will work for.
One problem that can arise with studying at the university is that it's time consuming. The students do not have enough time for family and friends. I think the best solution to this problem is to manage time.
"One problem that can arise with studying at university is that it's time-consuming."
Note: Just delete "the" because we're talking about the routine of going to university in general. Same with "going to work". If it's a more specific/immediate situation, we can use "the". For example, A: "Where's Dr. Peters? Oh, he's at the university finishing some paperwork." or B: "When I was young and in university, I used to regularly stay awake all night." < more of a general statement about a past routine
And for the last sentences, everything seems okay. Perhaps you could even use a hyphen and say, "I think the best solution to this problem is to improve one's time-management skills."
If you have any questions, you can send me a message any time!