Download and Install OpenJDK on Windows10

1. Navigate to https://adoptium.net/temurin/releases/ 
2. Use the drop-down boxes to filter the list of current releases based on your operating system and software requirements
   
3. Click on either the .msi or .zip buttons to download the files
   
4. The files will be downloaded to your computer and can be found in your Downloads folder

If you cannot find the pre-built OpenJDK version that you require, visit https://jdk.java.net/ for the the latest OpenJDK binary distributions and follow the Downloading and Installing OpenJDK on Windows 10 instructions below.

1. Download the latest OpenJDK binary distribution from https://jdk.java.net. Click the zip link next to Windows/x64 under the Builds section of the latest OpenJDK General-Availability Release. 
2. Extract the downloaded .zip file. The result is a new folder (e.g. jdk-20.0.1) created that contains the OpenJDK binary files. 
3. Move the newly extracted folder to a desired location.  
4. Start typing system environment in Windows Search, located at the bottom left of your screen.
   
5. Click Edit the system environment variables.
6. Click Environment Variables… 

Create/Edit JAVA_HOME

1. Click New… under the System variables section. (Note: If there is already a JAVA_HOME in the System variables list, select JAVA_HOME and click Edit… instead.
   
   
2. Type JAVA_HOME in Variable name.  
3. Enter the path of the extracted OpenJDK folder into Variable value. 
4. Click OK.  

Edit Path

1. Click Path in the System variables list. 
2. Click Edit… 
3. Click New. 
4. Enter %JAVA_HOME%\bin 
5. Click OK.  
6. Click OK to close the Environment Variables dialog. 
7. Click OK to close the System Properties dialog. 

Check the java version

1. Open a new command prompt window. (Type cmd in Windows Search.) 
2. Type java -version to verify the installation. 
3. Press Enter. You should see output similar to the following: