Assuming that you have been a PR way before Oct 2018, you will need to look back from the day you planned to re-enter Canada to calculate your RO.
If you left on Oct 2020, then if you come back in Feb 2023, then you still meet your RO assuming that you didn't travel outside at all before you left in Oct 2020.
As replied previously by another member, as long as you are not out of Canada more than
1095 days in the previous 5 years on the day your travel back to Canada, you still meet your RO.
How long must I stay in Canada to keep my permanent resident status?
To keep your permanent resident status, you must have been in Canada for at least
730 days during the last five years. These 730 days don’t need to be continuous. Some of your time abroad may count towards the 730 days. See
can my time abroad count towards my permanent resident status?