1. You need unity 2019.3.15f1 this version. Here you can download https://unity3d.com/get-unity/...
2. Unzip the project then click on File -> Open Project. Pick the project and it automatically import to unity.
3. Rename package
4. Set up the banner ad from admob. You can get banner_ad_unit_id from AdMob.
5. Configure Interstitial Ads fron admob. You can get ad_unit_id for interstitial Ads from Admob.
6. Enable Unity Ads and InApp in service window
7. Run App for test.