Need Assistance with Prepaid Phone Plans, Looking for Something Specific

Hello, everyone.

I'm new to the whole world of paying for phone usage and I like what plan my mother uses but I can't seem to wrap my head around all the numbers and bundles to find out what it is. I was hoping someone could help me understand.

I'm looking for a prepaid plan. I was originally looking for those pay as you go type of plans, but i'm confused from seeing monthly prices and everything because i thought you literally just "pay as you go." When i would watch my mother, she would often run low on money for her phone and she calls the company to put say $60 in it for continuous use. For every day she texts or talks, $2 is removed.

So why do i keep seeing monthly fees all over the website? Can anyone please clarify this process and help direct me to prepaid plans similar to the one i described? Thank you in advance.