How do you pay for bitcoin on Coinbase?

I'm curious to know, how exactly does one pay for Bitcoin on Coinbase? Is it a straightforward process, or are there any specific steps I need to follow? Do I need to link a bank account or credit card to my Coinbase account, or are there other payment methods available? Additionally, are there any fees associated with making a payment for bitcoin on Coinbase, and if so, how are they calculated? I'd appreciate any insights you can provide on the process of paying for bitcoin on Coinbase.