Choosing the right financial institution is very important when opening a checking or savings account. Most U.S. households are "banked", meaning they have either a checking or a savings account with an FDIC insured financial institution. An "underbanked" person is someone that does not have a checking or savings account with an FDIC insured institution, instead they use alternative financial services.
https://www.fdic.gov/getbanked/
The FDIC offers resources on how to open a bank account, checklists to pay attention to when in the process of finding the best account for your needs, and reasons to open a bank account.
https://www.helpwithmybank.gov/
The OCC’s HelpWithMyBank.gov provides answers to commonly asked banking questions.