In some scenarios, you cannot directly use .dmg files to mount and install applications. You can only find a way to extract the .pkg or .app in the .dmg file to install it. In this case, you can use 7-zip.

brew install 7-zip
7zz x x.dmg

If the decompressed file is a .pkg file, you can directly double-click it to install it;

If it is a .app file, you can copy and paste it into the application.