Doing Auto Brightness on a SSD1306 (OLED) Using APDS 9960 any idea how to do that ?

You might want to look at this How to get the best out of this forum before you proceed any further.

I moved your topic to an appropriate forum category.
The place you posted it is not suitable for asking for help with a project, it was for discussing projects already in the showcase area.

In the future, please take some time to pick the forum category that best suits the subject of your topic. There is an "About the _____ category" topic at the top of each category that explains its purpose.

This is an important part of responsible forum usage, as explained in the link above. The guide contains a lot of other useful information. Please read it.