In my opinion, there really is no safe way to continue using Windows 7 as your daily driver. My approach is to use Linux for that. The Wine program will allow you to use quite a bit of windows programs. Office runs perfectly on it, although there are great Linux-based alternatives, which will open Office docs, spreadsheets, etc. I love Windows 7, but at this point I go online very sparingly with it. My primary use of it is for my music composition. That machine is offline by default. Once Firefox support ends, I will probably just keep it offline permanently, along with my other Windows 7 machines or drives. That way you are totally safe, and can enjoy it as an archive, play solitaire, etc.

Of course, you can bite the bullet and update (I won't use the word upgrade in this case) to windows 10. That I will not do. not when Linux does everything I need, other than my music. Actually, it can even do that, but I've tried it and it's just not worth it.

As time goes on, the chance of being seriously compromised by continuing to use an unsupported OS on an ongoing basis is just too great. You're on very thin ice there.