What will happen to my IEEE conference paper if the status of the accepted paper is "AAR"

I think the flowchart in your question is pretty clear as to what happens next. But I'll break down the relevant part of the flowchart into words.

You have to make thorough revisions to your paper, and then resubmit. It will then be reviewed again. As a result of the review, it may be accepted, and it may be rejected.

AAR: your paper's current status - accepted after revising. It's now up to you to make the thorough revisions, and to then submit the revised paper

REV is the status your paper will have once you have submitted the revised paper.

RVI will be its status when the revised paper has been sent out to review. Judging by the flowchart, it will get sent to the same editor and reviewers as before, because a revised paper does not pass through the WFR stage of waiting for review, where reviewers and editor are assigned.

It may then be accepted (ACC), rejected (REJ), or conceivably, according to that flowchart, get returned to you once more as AAR for further revisions.

The flowchart also suggests that whether it's accepted or rejected, you still prepare a camera-ready version. That would seem to be very unlikely: I find it very hard to believe there's any use for a camera-ready version of a rejected paper; only an accepted paper would need a camera-ready version.

If the Journal/Conference editor/chair has accepted your paper, it is guaranteed to be published, given that you make the changes. That is the reason they emphasize the "review" part.

Some papers have only minor revisions, so if the changes are not made, it won't affect that much the quality of the conference. But if the changes are major, it usually indicates that you have to step up the level of the paper following the suggestion of the reviewers.

In conclusion, as long as you make the changes, your paper should be accepted in the conference, but if you neglect to do them, probably it wont.