Hi, so it depends on your country but generally military records are available from family history sites such as Ancestry and Findmypast, or (if you’re in the UK) some records are available from the government directly.

From records on family history sites, you’ll likely find rank and medal information. For boat and deployment etc you’ll need either more in depth info, or to cross reference info on which unit he served with (which you’ll likely be able to find out) with info on the history of that unit

Hope that helps!

Hello there! As your question is related to looking for identification/information regarding military personnel, our Guide on Military Identification may be of use to you. It provides a number of different resources, including how to request service records from a number of national agencies around the world, as well as graphical aids to assist in deciphering rank, unit, and other forms of badges or insignia. While the users here may still be able to lend you more assistance, hopefully this will provide a good place to start!