How do I make my .apk file smaller

I am trying to upload my app for the Oculus Go to the app store, but the apk file is too big. Currently, it is 1.27GB and I have an obb file and that is only 2.13MB. I was wondering how do I make the apk file smaller or move some of the stuff over to the obb file and take up more space there. Also, I am using unity.

Update:
I found the file that is making it so big. It is the sharedassets0.resource file and that is 1.23GB, how do I either move that to the obb file or compress it down