First - The manual may be online
Kubotabooks.com
Kubota usually puts out 3 manuals for each tractor a WSM - Workshop Manual, a Parts manual, and an operators manual. All 3 are well worth having if you expect to work on your tractor.
Based on the pics in your other thread those manuals or a credit card and a good dealer will be needed.
It's not rocket science, but it's also not sweeping floors.
There are three prime methods of PTO connections, sliding collar, pin and one other.
Here's an older primer
https://articles.extension.org/sites/default/files/NSTMOP Task Sheets Section 5 2013.pdf
Study that and Google a bit.
There will be a test when you try and unhook it.