Apps downloaded from the Google Play Store on your Huawei Mate 20 Pro are usually automatically updated from the Google Play Store if a newer version is available and you are connected to the Internet.
If you want to decide for yourself when to update an app from the Google Play Store, you should disable automatic app updates. This works as follows in the settings.
Disabling the Auto Update function on the Huawei Mate 20 Pro
1. Open the Google Play Store on the Huawei Mate 20 Pro
2. Tap on the symbol with the three lines in the upper left corner to open the sidebar.
3. Select "Settings" in the now opened menu
4. In the section "General" select "Automatic App-Updates".
5. Activate the option "Do not allow automatic app updates" in the drop-down menu.
Now you have deactivated the auto-update function for apps and applications on your Huawei Mate 20 Pro. These will no longer be installed by themselves.
Please keep in mind that you have to make sure that your app is up to date and that you are protected against security vulnerabilities.