Yes, you can use it. Never have I ever been in this situation = I have never been in this situation "I have never"... is used more frequently. "Never have I ever..." is more emphatic and literary, with the emphasis on "never". A typical way of saying the same thing would be ... "I have *never* been in this situation (before)." The speaker would place emphasis on the word "never". The speaker might also add the word "before" at the end of the sentence for emphasis. The word "before" is redundant, because "never" includes all the time up to now, but it serves to add some emphasis. Some speakers might say: "Have never been in this situation in my entire life." This also adds emphasis.

It’s typically when a person is surprised by something. Example: “Never have I ever seen a child eat so much!”

It has been said many, many times :) - redundancy for emphasis is not unusual. :)

Yes. It is a little odd, but some people say it to strengthen the statement.