hello I have just installed openwrt on my uz801 wifi dongle and I cannot get internet with my sim card knowing that it is to connect my carplay/android car radio via wifi and I have a French sim card (Bouygues Telecom) thank you for your help
This device doesn't appear to be supported by the official OpenWrt project. From where did you get the installation instructions and firmware file?
Along with the firmware question, check the simple mobile side too: the modem needs the correct APN for Bouygues and the interface must have the modem device actually detected before the radio/Wi‑Fi part matters. If this is a community build for the UZ801, it would help to post the firmware source plus the system log after inserting the SIM and the modem/interface page from LuCI. Without that, people may be guessing between unsupported hardware, missing modem packages, and just the wrong APN.
Test the card in a laptop or desktop running Linux before trying to use it with OpenWrt. This will confirm it is properly activated and compatible with Linux, and help identify the neceassry drivers.