Hi
This warning is just saying that your APK is larger than it needs to be. It probably contains both 32-bit and 64-bit versions of the app amongst other things.
The solution is to build an Android App Bundle (.aab) file instead. When you do this and upload it to Google Play, then when a user installs the app, Google Play will generate a .apk file specifically for the user’s device. So if the user has a 32-bit phone then Google Play will generate a 32-bit .apk file from your .aab file. The resulting .apk installed by the user will be smaller than the original .aab (and your current .apk) file.
See the following comment that @adamjnav sent to another user having the same problem:
Here’s another similar thread: