Good Business/Economics School

What would be the best schools to go to as an undergrad focusing on econ/business?

Your question is too opened ended. There are hundreds of school across this nation.

In a vacuum (where grades and cost are not a concern). Asterisks denote the very best:

Economics:
Brown University
Carnegie Mellon University
Columbia University *
Cornell University
Duke University
Harvard University *
Massachusetts Institute of Technology *
New York University
Northwestern University *
Princeton University *
Stanford University *
University of California-Berkeley *
University of California-Los Angeles
University of Chicago *
University of Michigan-Ann Arbor
University of Pennsylvania *
University of Wisconsin-Madison
Yale University *

Business:
Carnegie Mellon University (Tepper)
Cornell University (Dyson)
Emory University (Goizueta)
Georgetown University (McDonough)
Indiana University-Bloomington (Kelley)
Massachusetts Institute of Technology (Sloan) *
New York University (Stern) *
University of California-Berkeley (Haas) *
University of Michigan-Ann Arbor (Ross) *
University of North Carolina-Chapel Hill (Kenan Flagler)
University of Notre Dame (Mendoza)
University of Pennsylvania (Wharton) *
University of Texas-Austin (McCombs)
University of Southern California (Marshall)
University of Virginia (McIntire)
Washington University-St Louis (Olin)

To get into most of those schools or programs, you are going to need a 3.8+ unweighed GPA while taking very challenging courses (IB, A Level, AP etc…) and SAT/ACT scores over 1400/32.

Economics

https://ideas.repec.org/top/top.uslacecon.html

https://ideas.repec.org/top/top.usecondept.html

US News and World Report rank UCBerkely Haas and MIT tied for second in undergrad business education and UPenn Wharton as first.

So you’re asking for school recommendations? You should list off stuff about yourself.
Hooks, extracurriculars, state you’re from, parent’s budget, things you care about in a school. There’s so many business schools in the US.

UC Berkeley is top tier in both.

Many many schools can fit the bill. To get any meaningful suggestions you need to give additional information such as academic stats, budget, preferences etc.

In the meantime one way to narrow things down is to decide if you want to study economics or business as they are very different majors. Economics is a liberal arts course of study and gets very theoretical at the upper levels. In contrast if you go to an undergraduate business school you will take a business core with introductory classes in subjects such as accounting, finance, IT, marketing etc. and then you will major in one of those disciplines. I’m not saying that one path is better than the other, but they are different. I would take the time to look at the coursework (can be found online) for both a finance and an economics major and see if one path is preferable to you.