Can I have 2 internet cable services at the same time

Hi,

I plan to have additional internet service as backup in my new apartment.

My question: can I have 2 internet cable services from 2 different companies at the same time? I believe there is only 1 cable line in the new apartment.

If not, I need to order DSL internet as backup. Verizon offers phone and internet service together. One question: can I use the phone and internet at the same time? In my current apartment, there is so much noise in phone when I am online.

Thanks.