Hi Nithin
1. Unfortunately, there is no standard functionality in PI to convert to XLS format. As to whether the bank can convert from CSV to XLS, that you will have to negotiate with them directly - it really depends on whether they are willing to do it.
2. For SFTP/FTP connectivity you will need to request for the server details and login credentials. For PGP, you will need to get their public key - refer following blog
PGPEncryption Module: A Simple How to Guide
Rgds
Eng Swee