Help! My First Android App Development Is a Mess!

Hey everyone! So, I'm trying to build a voice clock app for Android, similar to the Miku or Gumi voice clock apps, because I own Gumi for SynthV and I want to create custom lines in English. I dove into Android Studio with almost no sleep and with very little programming knowledge—and it's been a wild ride! I've been getting lots of errors and I'm not sure how to fix them. The app should use audio recordings to announce the time at specific intervals (like every 5, 10, or 15 minutes) as well as custom alarms for things like taking medication. I've linked my GitHub code for anyone who's interested in checking it out. I could really use some guidance since I keep encountering unresolved references and warnings about properties that are never used. I'm starting to think I might be in over my head here! Any advice?