This is my first forum by myself only.

My mate said Forum page seems not exsist.

Do I need to more settings except for "Categories and Forums Add New" ?

As long as my searching with Google, it seems not requird to do anymore steps.

Could you help me ?

@surlofia,

I see that you have JS errors in your website, please fix them first. And also try another theme for better forum look. Example Astra, Shuttle iBusiness …

@chris

Thank you.
I was able to solve the problem.

It seems that installing wp in a subfolder of the wp folder is not working.