I've been working with some storage issues recently, so this article is timely, and while much of the advice in here...

I've been working with some storage issues recently, so this article is timely, and while much of the advice in here is good, do yourself a favor and download Google's own Files to Go app and let it go. Just make sure the data is backed up before erasing anything from your device.

https://play.google.com/store/apps/details?id=com.google.android.apps.nbu.files


https://www.pcworld.com/article/3080036/android/6-quick-ways-to-clear-space-on-an-overstuffed-android-device.html