How do blogs inherits the master theme settings?

You manually edit each site.

Every site has it’s own settings. They’re separate.

I want some thing like (new blog defaults) plugin ,but for theme settings ..

The best we can do is suggest the blog-copier plugin, which copies it all over to a new blog.

I want the user register the blog himself not have it copied by superadmin

https://www.ads-software.com/extend/plugins/wpmu-new-blog-defaults/

They say they can do theme settings?

this plugin is Compatible up to: 3.1.4 , however I used it
it only worked as theme name selector not theme setting !!!

Don’t get hung up on that compatibility thing. It’s wibbly wobbly.

You’d going to have to do your own legwork here, and look for more plugins like that one, then.

I tried this plugin :
https://www.ads-software.com/extend/plugins/wpmu-new-blog-defaults/

it is only sets theme name for the new blogs NOT theme settings

If there any plugin takes the settings !!!