If you feel the need to clean your phone occasionally, I'd recommend just using the Device Maintenance Utility on the edge menu. I rarely use that one but once in a while I will. It's made by Samsung for your Samsung.
As far as antivirus if you are concerned about that... I do feel that Android is more vulnerable to the possibility of virus than iOS but that is depends on user and if they do stuff like side load apps and such. Don't know about McAfee but my .02 cents, I read and decided on BitDefender when I got my Note 8 after preordering two Octobers ago and it's been running in background since and forget it's there. A little piece of mind for me. And I have Google Rewards installed making Google Pay money from periodic surveys so it pays for the yearly fee for BitDefender.
I also use AdGuard for blocking ads in browser and apps and all these apps have run in background without an issue for over year. AdGuard if you keep an eye can find deals... I got 2 PC + 2 Android lifetime license for $25.
I feel those apps are the best combination and pretty much all you need.