Hi @plambojon. Welcome to our community forums.
Did you check our Determining the server upgrade path docs?
Quoting it:
- If there is at least one LTA version in your upgrade path, you must first upgrade to each intermediate LTA and then to your target version.
Meaning that you will need to go to 8.9, 9.9, and then 10.5.1 (or 10.6.0)
Just make sure to backup your DB, as stated in our upgrade roadmap.