If you want to include a complete set of icons for Android:
icon-72x72
icon-96x96
icon-128x128
icon-144x144
icon-152x152
icon-192x192
icon-384x384
icon-512x512
There is some helpful tools like https://www.simicart.com/manifest-generator.html/, to create icons.
For iOS, you will need:
icon-120x120
icon-180x180
With square background (can’t be transparent background).
A good repository for references at https://github.com/gokulkrishh/awesome-meta-and-manifest