It might be out of date, but it will have nothing to do with this site. Presumably you are on a PC
Suggest you ensure that you are running the latest patches for Windows, and after the computers installed all that, install something like ‘malware bytes’ and do a scan.
flash is dead technology, but it’s likely you have an infection if ‘keep getting’ is an accurate description of the popup. Don’t click on anything it asks you to.