> Task :app:compileDebugJavaWithJavac FAILED

It all started when I used this command because my native base library was not working properly: npm install @ react-native-community / picker --save

I've tried everything and this error keeps showing up, even in newly created projects. It just does not occur in projects that I already had and, when changing the name of the project folder, it also occurs and there is no going back. Even copying the entire project that already works, it happens (which makes no sense).

Can someone please help me?

Error description:

Deprecated Gradle features were used in this build, making it incompatible with Gradle 7.0.
Use '--warning-mode all' to show the individual deprecation warnings.
See https://docs.gradle.org/6.2/userguide/command_line_interface.html#sec:command_line_warnings
11 actionable tasks: 2 executed, 9 up-to-date

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':app:compileDebugJavaWithJavac'.
> Could not find tools.jar. Please check that C:\Program Files\Java\jre1.8.0_261 contains a valid JDK installation.

* Try:
Run with --stacktrace option to get the stack trace. Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Get more help at https://help.gradle.org

BUILD FAILED in 55s

error Failed to install the app. Make sure you have the Android development environment set up: https://reactnative.dev/docs/environment-setup.
Error: Command failed: gradlew.bat app:installDebug -PreactNativeDevServerPort=8081