I don't have experience myself with affinity software specifically but here I found a step to step guide on how to run it on Linux:
Like the other person said, Wine is the way to go to run Windows specific software on Linux.
The cool thing about Linux is that you always find a guide for whatever problem you may have and also the community is huge and super nice to help you with any issue.
Also you can always have Linux + Windows with dual boot and try out things until you are comfortable to do the change, or just abandon Linux if it is not your cup of tea, but at least you have tried.
We may have to just accept that it won't ever be a big platform for this very reason and just have fun there as a niche site.