A pop-up should appear saying: "The current version requires macOS 11 or later, but you can download the last compatible version." Click . Method 2: Trusted DMG Downloads
: Allows for editing at resolutions up to 4K, though it is limited to 4K 30fps (it does not support 4K 60fps or HDR video on Mac). imovie 10.2.5 dmg download
After successful installation, you can delete the DMG file to free up space. A pop-up should appear saying: "The current version