Blind Mac Mini server remotely logging in at start when File Vault is active - how to?

[Change Agent]

I have a Mac Mini as a blind server (normal OS11). I would like to have File Vault activated. Presently it is now because in case of a power failure or so it will not boot up without me needing a password.

Now all this would not be a big problem if:

• It was not a blind server.
• It was easily accessible (it is located in a storeroom on the top shelf in the back)
• And it would be a pain to hook a screen up to it (as said storeroom – there is no space to connect a screen of normal size)

Now when it reboots, I think it will not be available in screen sharing or for example in TeamViewer.

So, either I find a cheap (very small very cheap) screen (I have not been able to find one) that is permanently hooked up and connect a keyboard when needed. Or connect to the Mac Mini when it asks for a password at login.

Anybody know or have a solution? I hope so!