So I am able to get questions with specific tags, but still not able to get questions which have specific text and a specific tag.

For example if I want to get all the questions with text "api" in the title and they are tagged with rest, what should be the best API call I should use?

Also, I saw that webhooks request was declined by Stack Overflow a long time ago, but it was in 2010. Is that something on Stack Overflow's pipeline?