Absolutely required:
State your sins
Receive absolution
The rest is important but not essential/required. Telling the priest how long it’s been helps guide him in advising you.
Edit to add, since you’re new here (welcome, btw!):
If you don’t at least attempt to follow the normal format, it could cause the priest to sort of raise an eyebrow and begin guiding you through the process, assuming you haven’t been in ages. In such case, he’s probably going to ask. Might as well just start off on the right foot and do things per the “normal” order.