The purpose of PoF is to show that you have the minimum required funds to settle in Canada as per your family size. You can show any account in which you have the requisite funds or show multiple accounts to show that they combined have the funds. You will also have to disclose any loans you may have.
As per CIC for the PoF:
Purpose
To confirm whether the applicant meets the low-income cut-off (LICO), assessed by the amount of money they hold compared to the number of people in their family
Document requirements
The applicant should provide an official letter(s) from one or more financial institutions that lists all current bank and investment accounts as well as outstanding debts, such as credit card debts and loans.
o The letter(s) must be printed on the letterhead of the financial institution and must include the applicant’s name, the contact information of the financial institution (address, telephone number and email address), the account numbers, the date each account was opened and the current balance of each account as well as the average balance for the past six months.
Other documents may also be requested, as necessary.
Individuals who must submit this documentation
The principal applicant