Can't install WhatsApp on iPhone

That’s correct. Your iPhone 5s can’t be updated beyond ios 12. You need a newer phone.

If your 5s is running iOS 12 or later and if it has a valid SIM card traffic plan, it should support Whatsapp.

What happens if you try to download it from AppStore?

Are u getting an error message?

Have you contacted your cellular carrier and asked them about this problem?

Giorgi0011,

what error message are you getting if you try to download it from AppStore?

In what country are you trying to use it? Have you seen this article?:--> https://www.cloudwards.net/countries-where-whatsapp-is-banned/

My pleasure