Not a dumb question at all! In Europe I’ve seen a few training programs held by companies looking to get new talent in to learn from the older techs. Browse around and see if any companies around you have something like that.

There are some free resources available that will allow you to get training but I haven’t tried them myself. IBM Z Xplore is worth a look as an example: https://www.ibm.com/products/z/resources/zxplore

I hope you find a way in, more mainframe developers and sysadmins(often called systemsprogrammers in the mainframe niche) are always needed.

Edit*: Spelling and grammar