This is how Ja-En course looks like
Step 1- Go to the home where you would do your lessons.
Step 2- Go to the flag icon next to your name and bring down the drop down menu.
Step 3- Right click any language and press inspect element.
Step 4- You will see multiple lines with "language choice etc." in them
Step 5- Choose one and replace the two letters near the end with "ja"
Step 6- Collapse that specific line even further and replace every two letters of the original language with "ja"
Step 7- There will be a line with the full spelt out name of the original language. Replace that with "Japanese"
Step 8- Go back to the drop down menu and select Japanese.