Topic: Windows 10

[Always THE HERD]

I previously had Windows 7 and had 10 installed on my desktop by a local computer repair shop a few years back.
I have 2 questions:
1. Windows security is recommending for virus & threat protection I set up OneDrive for file recovery options in case of a ransomware attack. Account protection, firewall. network protection, device performance, health, app & browser control are already installed on my desktop and actively running.
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Shop I setup OneDrive or not???
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2. I also have Seagate Backup Plus external drive installed....BUT I keep getting a reminder "only 4 of 9 are backed up". How do I know which ones wer not?
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I seem to be "a lost ball in high weeds"....can some of you computer nerds help this senior citizen out?