No almost certainly you will recover it quite easily.
This happens when eosinstaller fails (for whatever reason) the phone is not broken if you have a working Fastboot mode. The flashing of both recovery and system failed. You can check any of the other threads with hashtag eosinstaller to read previous advice.
Beware, did you fully take in the anti-rollback hazard? See below.
Regular manual command line install page Install /e/OS on a Fairphone The Fairphone (Gen. 6) - “FP6”
PS
You must not be alarmed at this. The phone will be unlocked for the duration of the install process.