Drupal 8.x

Hello.

It is possible that my question will seem stupid, but I can't find information anywhere on how to properly remove the module installed using the composer. Drupal version 8. Where can I read about this?

With respect.

Hi!

I'm using GoDaddy to host my page, and i've installed Drupal 8.7.11.

But there's no button for "Install new theme".

I've delete it, re installed, installed older versions.. and still there's no button for installing a new theme, how can I make it appear?

Is there some other way to install the theme?

Thanks.

I'm searching a media browser for documents with a filetree like windows explorer. How can I do this?

I tried to migrate Rest services custom module, that processes POST requests, from drupal 7 to 8. 
But can't get POST to work, route not found error.

The GET is working, but POST give path error. I tried to follow the instruction given at below link
https://www.drupal.org/docs/8/api/restful-web-services-api/custom-rest-r...

<code>
/modules/custom/tax_tob/config/install/rest.resource.demo_resource.yml

I tried to migrate Rest services custom module, that processes POST requests, from drupal 8 to 9. The GET works by following instructions
But can't get POST to work, route not found error.

The GET is working, but POST give path error.

I follow the instruction given at below link but not fruitfull.
https://www.drupal.org/docs/8/api/restful-web-services-api/custom-rest-resources