Yoast SEO no longer uses meta keywords for SEO purposes, because Google and most major search engines don’t use them for ranking

But it’s okay to add them if you want.
Yoast SEO focuses more on title, meta description, and content keywords — which help ranking better

1. Open WordPress Dashboard

2. Go to Yoast SEO → Settings → Advanced

3. Turn ON the option called “Use meta keywords tag”

4. Go to any post or page you want to edit

5. Scroll down to the Yoast SEO box

6. You’ll see a field called “Meta keywords” — type your keywords (separated by commas)

7. Click Update/Publish

   https://emeesha.xyz/