Java Edition and Windows 10 Edition are not compatible . It is impossible to play together unless one of you switches to a version compatible with the other: either he switches to Java Edition, or you switch to Windows 10 Edition. Java Edition and Windows 10 Edition are not compatible.
Read moreHow do I switch to Minecraft 1.8 9?
How to Downgrade Your Minecraft to 1.8
Read moreHow do I upgrade to Java 16?
Java 16 – Download and Install Oracle JDK 16
Read moreHow do I uninstall Java 1.8 on Windows?
Manual Uninstall
Read moreHow do I update Java 1.8 on Mac?
Update Java in the Java Control Panel
Read moreHow do I change my version of Java?
In the Java Control Panel, click on the Java tab. Verify that the latest Java Runtime version is enabled by checking the Enabled box. Click OK in Java Control Panel window to confirm changes and close the window. Try to run same applet and verify it is now running using latest version of Java installed in your system.
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