Transfering files from older to newer version

I would like to know how to transfers files from a 2018 version of Sketchup to a 2021 subscription version of Sketchup on a different computer. Can anyone tell me how to do this?

Email. Usb disc, synctools(google drive,dropbox, etc) Trimble connect, etc. etc.

Any version of SketchUp can open older versions than itself