For all open competitions published after 1 January 2025:  

You only need to fill in your CV details once (under “My account” → “My CV” in the Single Candidate Portal).
The information saved in your CV will be used for all future applications, so please make sure to keep it updated.

For contract agent selection procedures:

No, you must fill in a new application form in your EPSO account for each selection procedure you wish to apply for.