What is Folio in accounts?

Very well yes. The folio number of a MF is like the account number of your bank. You can get all the details you want using it.

Capital account increases when capital is introduced, shares are issued, increase in retained profits, etc.

Capital account as well as Drawings account are Personal accounts !!!

the accounts payable account is on the general ledger and is generally comprised of many smaller vendor accounts which are listed and tracked separately in the "accounts payable subsidiary ledger"....

A Drawing account is a contra capital account and is used by a proprietor type business. It is for recording the owner's withdrawals of the company's assets.