OCLP on 2016 MBP 15-inch

Hello all, I’m new here. I have a MBP 2016 15 inch. The last version installed is Monterey 12.7.6

I want to update my Mac to Sequoia. However, I’m concerned regarding security. (I’m a newbie to this, so please be kind). My aim is to use this Mac regularly. I’ll have iMessages enabled and other iCloud services and store some personal files as I don’t have another pc or Mac and can’t afford at the moment. What are the security and data risk here of using OCLP?

Should I take a backup of my Mac(its factory reset as of now, moved data to iCloud to my another Apple ID) right now just in case it gets buggy or have any issues later?

Anything else that I should know that helps me before I proceed?

Many thanks