Well, given that your oath invite can come in anywhere from one day to 6+ months, it's not a bad idea to start thinking about the passport application and be ready to act quickly once you get the oath invite.
Read the
instructions for applying for a passport. In particular, start thinking about whom to ask to be your
guarantor and reference. The guarantor is most important to think about ahead of time, because it needs to be a Canadian citizen who has a valid, non-expired passport, has known you for at least 2 years, and is okay with signing your application, one of your photos, entering their passport information on your application, and agreeing to be called about you. It took me some time to come up with candidates, as almost all of the people I know well enough who would agree to that are other PRs or non-Canadians.
References are easier to find, as they only need to have known you for at least 2 years and agree to be called about you. They don't even need to be Canadian or in Canada.
Also, now is a good time to make sure you have good pair of scissors to cut up your PR card during a virtual oath ceremony, and that you and everyone in your family have
proper ID for the oath.
You can read this page on preparing for the oath, although it is targeted to in-person oaths. But a growing number of offices have been having in-person oaths recently, including
Ottawa
https://www.canada.ca/en/immigration-refugees-citizenship/services/canadian-citizenship/become-canadian-citizen/citizenship-ceremony.html