You can continue to run all your old apps on any of the current Intel Macs (but not the new M1 Apple Silicon Macs). You just need to setup a MacOS virtual machine. This is what I do, running Catalina on a 2018 Mac Mini, I have both Mountain Lion and Sierra virtual machines and they run all my old (very expensive) 3d, CAD and database software really well - considerably faster than they ever ran natively on my old Macs. I also have a 2008 15" MacBook Pro, but gave up on it long ago so it just sits in the closet now, with a dead battery.
I also had Office 2008 and it was running fine under Sierra, but crashed frequently with big documents. This got too frustrating, so I upgraded to Office 365 and have been really happy with it. Like everyone, I hate subscriptions, but this one was worth it. For $100 a year you get all the Office apps and can even give 5 copies to your friends/family. Maybe you know somebody who already has it and would be willing to give you one of their extra copies? AFAIK, there is no restriction on who you can give copies to. Each person also gets 1tb of Microsoft OneDrive storage. This all seems like a very good deal from Microsoft.
My old version of Photoshop also ran under Sierra, but was also crash-prone. Got tired of that and got the Adobe Photography plan, which is also reasonably priced although not as good a deal as Office IMO.
Anyway, you should still be able to run all your old apps in a virtual machine with Parallels (maybe other ways too, don't know). Parallels isn't free, but has been well worth the cost for me. I also run a Windows 10 virtual machine which has completely replaced my old Windows computer, and is also much faster.
