high level steps for newbie to apply first PRP or patch to (then through) PUM

As a PUM newbie, please help me understand the process for applying a one-off patch (PRP).

Steps taken thus far include:
1. installed latest PUM
2. patched environment(s) to the latest PUM
3. downloaded one-off patch

Do I next use CA to run the project found in that patch to apply it to my PUM, followed by then creating a change package to apply back to my demo and then higher environments?

Thanks.

-- M --

Bonus points: While I am anticipating relatively high-level/generic directions, my specific effort at this time is to apply this patch in this environment:

• patch 29489593: 2019 - 2020 AID YEAR UPDATES FOR FISAP REPORTING