How to Uninstall System Apps without Root in Android

1. Activate Developer Mode on your phone 

Go to About Phone. Then tap 7 times on the Build Number, until you see the message — You are now in Developer mode! (This procedure may not be same for every smart phone)

2. Now, go to Additional Settings and enable USB debugging.

3. Connect the phone to the computer using a USB cable.

4. Download ADB Installer and Platform Tools (Windows | Mac | Linux) . Unzip both files. Install, ADB-setup.exe file.

5. Open Platform-tools folder in your Computer .By pressing Shift right-click the mouse and click on “Open Powershell/command prompt window here”. See the image below: 

6. Type adb devices and press enter. You’ll get a prompt box on the phone. Check the “Always allow… option” and grant permission. Then the Powershell/command prompt window may show as shown in the image below.

7. Enter adb shell  and press enter .This command may display your device model name. I'm using Realme phone. Hence code begins with RMX.

8. To uninstall a package ,next to the $ sign, type command like this pm uninstall - k --user 0 com.google.android.youtube and press enter. This command will uninstall YouTube app. 

9. Success message will be shown.

To see all packages name installed in smart phone , use the command  pm list packages

I've removed following apps from Realme using the command shown below it's package name

FinShell Pay 
pm uninstall -k --user 0 com.finshell.fin
Browser
pm uninstall -k --user 0 com.heytap.browser
DocVault
pm uninstall -k --user 0 com.os.docvault
Facebook
pm uninstall -k --user 0 com.facebook.appmanager
pm uninstall -k --user 0 com.facebook.services
Lock Screen Magazine
pm uninstall -k --user 0 com.heytap.pictorial
Oroming
pm uninstall -k --user 0 com.redteamobile.roaming
Cloud
pm uninstall -k --user 0 com.heytap.cloud
Music
pm uninstall -k --user 0 com.heytap.music