Visit the Store. There are filters, and search to easily find blocks.

To publish a block, your block has to be first deployed. Go to the manage blocks page and find the publish button. You will then fill a form and wait for Appblocks to review and publish your block.

To install a block, you have to have installed the bb-cli first. Go to the block details page of this particular block and find the installation command on the right hand side of this page. Copy and paste it in your CLI.

The reason for rejecting a publish request will be shown in the review status tab of the Publish a block page.

To delist a block, go to the manage blocks page and find the delist button. If you don't see the delist button, it means that your block is not published.