If you want to find out the name of the theme a website is using that is powered by WordPress CMS, you can do so by following these simple steps:
1. Right-click anywhere on the website and select "View Page Source" or Press "Ctrl+U" from the keyboard. 2. Now Press "Ctrl+F" from the keyboard. 3. Search for "themes" in the search box. 4. Theme name will be shown like "themes/THEME-NAME" copy and enjoy.
I hope this helps. Let me know if you have any further questions!