Advice on bills, banks, mail, and markets (Lisbon)

Hi everyone,

I have finally made the move to Lisbon and have been settling in the Alfama district for the past week. However, I am facing some complications such as figuring out how to pay bills (just got a phone plan with MEO and they told me an "invoice" will be mailed to me and I could pay it off using the multibanco?? Also, could American credit cards be used to pay the Lisboa Viva card?), which bank to go to to open an account (I'm also a student here... so any kind of student benefits would be great. Also need a bank with a US based affiliate to make transfers from my small american bank), where to send mail and good supermarkets in the area.

Any kind of advice would be much appreciated. Obrigada,

Ariana