Diagnosis
Yeah, this one's common. The internal storage on these models is pretty limited, and the OS and updates eat a big chunk of it. Once it's near full, everything gets sluggish and apps fail.
How to Fix It
Go to Settings > Device Preferences > Storage. Clear the cache for individual apps (especially large streaming apps). Then, uninstall any apps you don't absolutely need—pre-installed 'channel' apps like Pluto or Tubi can often be removed. The biggest win is to manage automatic app updates: in the Google Play Store settings, turn off auto-update for apps.
If That Didn't Work
You need a more nuclear option. Go to Settings > Device Preferences > About > Factory reset. This wipes everything back to out-of-box, including all your logged-in accounts. It's a pain, but it's the only way to reclaim the maximum space.
Heads Up
Adding external storage via USB doesn't help for installing most apps. The USB port is mainly for media playback. You're stuck managing the small internal pool.