Why does iPhone 13pro keep dropping wifi signal

When does it drop Wi-Fi? All iPhones drop Wi-Fi when the screen locks to prevent excessive battery drain, unless the phone is connected to power. If it does it when using the phone, try turning off Wi-Fi Assist in Settings/Cellular.

Beyond that, you will have to do some troubleshooting. Start with restarting your router by turning it off for a few seconds. Next try forgetting the network and then reconnecting. Beyond that Reset Network Settings.

Does this only happen with your home Wi-Fi network, or all wi-Fi networks?

It shouldn’t take more than a couple of seconds when it wakes. Is there a difference based on signal strength; that is, the same close to the hotspot and further away?

also: how old is the router, it’s it a single router, does it have a range extender, or is it a mesh network?

And what about when it drops? Only when it goes to sleep, or while you are using it?

And what was the result when you tried each of the troubleshooting steps I posted?