Can i get facetime on my ubuntu or linux?

I suspect it's some sort of scam. Apple has never made a version of Facetime for any operating systems except their own. So, this is not an "official" app, despite what the site claims. I'd be concerned that it will install malware of some sort. And, it won't work.

That's a third party application. It mentions it runs on Windows (not Ubuntu or any other flavor of linux).

And I would not trust it for a second, as Facetime is a closed protocol Apple has not, to my knowledge, made available to third party developers. So not entirely sure how that App for Windows works or if it even works at all and is not actually just a way to deliver a bunch of nasties to the computer that installs it.

Read here:

https://www.lifewire.com/can-you-use-facetime-on-windows-2000762

No. Facetime is only available on macOS or iOS.