Am I correct in thinking that all fire doors in towers blocks must be FD60 rated, and if so, do they have to meet a specific BS EN grade as I have seen a few online UK stores saying there FD60 fire doors come with a fire door BWF certificate, or is this the equivalent to a BS EN standard.

Approved Document B of the Building Regulations is your guide - appendix B and Table 1 gives test methods and resistance figures https://www.gov.uk/government/publications/fire-safety-approved-document-b