How to config App name
Open file android/app/src/main/res/values/strings.xml and change to your App name.
How to config build version and application Id
Open file android/app/build.gradle and change to your name own.
More Info ApplicationId: https://developer.android.com/studio/build/application-id
Note: After change the ApplicationId you need update file android/app/google-services.json you can navigate to step Login Google to know how to create and download that file.
How to change Splash Screen Image
Replace all images with same size in folder android/app/src/main/res/drawable-*
Don't forget clean cache after change app info.
cd ./android && ./gradlew clean