In the U.S. most credit unions are regional, if you go to a branch you can withdraw cash easily, or they’ll have agreements with ATM networks where you can withdraw cash for a fee, just like banks do.
In my daily life my credit union is indistinguishable from a bank, with the exception that I’ve had a few auto loans from my credit unions and they’ve always offered a lower interest rate than anything a bank or car dealership can beat. They also gave me a discounted rate because I was buying an electric car.