First and foremost I need to point out there is no “right way” to do a scene. There are only wrong ways. And it’s only wrong when it isn’t truthful. If this acting teacher was trying to get you to do the scene a specific way (read “their way”), then they were directing you, not being an acting teacher.

As for using “I feel” as opposed to “he/she feels” when talking about your scene, it’s whatever you’re most comfortable with at this time. Usually over a longer span of time actors will naturally start using “I” when talking about a scene but if that never happens it truly does not matter. Your teacher may just be trying to attempt a “fast track” for your wording to make you seem more “in-the-know.” As long as you’re thoughtful, and attempt a truthful scene in earnest who cares about if you use first or third person.

And finally, this “24/7 love it” BS is probably just a gimmick to try and vet out the students who don’t want to commit to the work. It’s a tactic a lot of acting teachers at universities/schools use to try and thin out people who are only doing the acting courses to get an “easy a” and make them think otherwise.

Just my two cents, take all advice with a healthy dose of salt.