how i change my nat type

I don't think you can change this on the device. If you are using your iPhone without wi-fi the NAT and the ports required to do this might be dictated by your ISP. You will also very likely be lagging in any on line game and unless you want to ruin a match for everyone you should probably consider a better option. Your not browsing the web on the PS4, don't commit everyone to wait for your dial up speed to sync because you lack the bandwidth to make it enjoyable for everyone.

Recommended settings for Wi-Fi routers and access points - Apple Support

If your goal is to change the NAT type to type 1, you will not be able to do so with the iPhone providing a hotspot for Internet access. That is because, the iOS Personal Hotspot feature uses your cellular data plan for Internet connectivity.

You will need a dedicated wireless router, connected to an Internet modem or gateway, that can support the UPnP protocol.