Trojan.Backdoor Activity 114?

Today I was on Youtube as normal and suddenly it said "your connection is not private" after about 5 minutes NortonLifeLock then continuously "prevented an attack" (see picture)

I don't know what to do about it and I'm terrified that this virus could cause something worse.

I look forward to answers and thank you in advance (:

(if it is important I have a Toshiba laptop with Windows 7)

A) hope that Norton really blocked that part and that you haven't caught anything

b) update to Win10. Win7 has not received any security updates since January, which may have led to the "attack"

c) create a backup that is also virus-free