Nat on FortiGate 60F

Hi

I tried several times reading about how NAT works in Fortigate, but it doesnt work.

FortiGate 60F, firmware 7.2.8 build 1693.

I found many guides using "IPv4 policy", but this is not present in my "Policy & Objects" menu, I think maybe different firmware.

So I create Virtual IPs I need, then I create firewall policies from wan to virtual ip.

But it doesn'n works, i presume i made something wrong o I didn't do at all something that is necessary.

I am new in FortiGate, coming from other manifacturer products, any help is welcome.

Edit: I add some informations may help:

System is in NAT mode.

Gateway is a modem/router Fritz, and Fortigate is in DMZ on it.

Activating https admin on wan interface, it is reachable from internet.