Don't worry too much about the "tier" of your university
I'm saying this from the perspective of someone who finished their undergrad in CS and is now in law school, the actual university you went to in Undergrad is not going to dictate how your career ends up, even if it may have some impact.
From a computer science perspective:
I did my undergrad at a university people consider to be "mid-tier" and I took basically all the same classes and essentially learned the same things as my friends in Waterloo CS. It is true that a lot more Waterloo CS people end up working in California, but I would honestly attribute that to the culture difference; people in Waterloo CS are the ones gunning for those US jobs, grinding out the leetcodes, and applying for any opening in the US. There's simply less people doing that in other universities, but like, there's nothing stopping you from doing the same grind. Most of the interviews in those companies test your raw technical abilities, and the actual university you are from very rarely going to be a determining factor. I will say though for CS try to pick a program that has co-op.
From a law school perspective (also applies to med school); the uni you go to will usually have zero impact on whether you get into either of these schools, just focus on getting good grades in whatever program you are in.
And just in general, sometimes people may favour some universities, but for most employers it's not really going to be a big factor (with the caveat that employers in a certain city will generally favour candidates who live in that city already because they don't want you to just do an internship there and never come back)
I just want to say, a big congratulations to anyone who got into any university, and know that your university is going to be a small factor among many when you ultimately try to find work.