how can i select the best university (4 year) possible?
You have given absolutely no useful information with which to offer advice.
The best college for you is one you like and can afford, and that you can get into to. Without knowing where you want to be, what you intend to study, what vibe you are looking for, stats, finances, etc…we can’t advise you.
If you have residency status in some US state, then you might want to start by checking out your state flagship. These schools tend to represent an excellent balance of high quality and relatively reasonable net cost for state residents with good stats (typically, >= 3.5UW and >= 1300 SATs … but on the higher end of those ranges in a few states such as Michigan, Virginia, and CA).
If your stats are excellent and you have interesting ECs, and if you think your family can afford the net costs, then you might want to have a look at the 8 Ivy League universities. If you think you’d prefer a smaller college, then check out a few of the NESCAC schools.
All of @Lindagaf’s caveats apply. Depending on your budget, interests, and personal preferences, there may be better alternatives to any of the above. The Ivies and NESCACs are all in New England or the mid-Atlantic states; many fine alternatives are spread throughout the USA.