Set Microsoft Copilot as the Default Assistant on Android
First,
Click on the Link
and go to PlayStore Copilot Page, Join the Beta Program.
Joining the beta program will take some time, wait for some time and once you got the confirmation, Download and install the Copilot app.
Once you Installed Copilot, Go to Settings > Apps
Under Apps tap on Default apps
Under Default apps tap on Digital assistant app
Under Digital assistant app, Choose Copilot
That's it we have set Copilot as Default assistant on Android