Premiere pro extensions menu not appears

Hi There,

I have just purchased premiere pro. After i  installed premiere pro 22.6.2, once I open that there is no extensions menu. I tried to install some extension from adobe Exchange but after installation was successful I open premiere pro again and its the same!

Did I do something wrong? Where is the extensions MENU?? 

Please see the attached video.

Premiere pro Version: 12.6.2 (build 2)

MacBook Pro (13-inch, 2017)