Guide

1. Head over to Plugins in the left sidebar of your WordPress dashboard.

2. Select Add New from the dropdown.

3. Search for Robots.txt in the plugin marketplace.

4. You can select and install any of the robots text editor apps. Let's go with Robots.txt Editor

5. After installation, head over to Settings>Reading in the left sidebar.

6. To block the Semrush bot type:

   User-agent: SemrushBot

   Disallow: /

7. Finally, clear the cache by going to Toolbar > WPRocket > clear cache to set things in motion.