Ah, didn’t know you are doing this directly in MobileApp.
I suggest to use the app store first. Search for a brand, then you will get one ore more apps showing up.
Select an app an check the supported devices. Tuya is Wifi based, so the MobileApp can’t search a device like it’s possible for Zigbee.
The official app is currently broken, but with some luck, Athom will add a new login. You can subsribe the tipic above to get updates. That’s the easiest way.
When using the community app, it’s much more work… You need a Tuya developer account and if the dehice is not direct supported, you have to work with flows. Most is described in firt post of the app thread.
That’s why I would wait some time if the official app comes back.