Unfortunately it is not really feasible to get Microsoft Office working in Zorin right now, in fact I'd say this is one of the bigger pain points for people transitioning from Windows. I've tried almost every solution proposed out there and they either just don't work or come with massive trade-offs that make it not worth trying.
There are alternatives though that you can use, that will generally accomplish the same things:
- For an alternative to Outlook, I recommend Evolution, which more-or-less aims to be a drop-in replacement for it. Very similar feature set. Otherwise, there is Thunderbird - there are also lots of other clients that are more focused on just being a good email client like Geary or Mailspring.
- For a OneNote replacement, check out Joplin. If you have a OneDrive account, you can sync your notes up with it, and there is a mobile version of it too.
For word processing, spreadsheets and slide presentations, my picks are, in order of preference:
- WPS Office is, by far, the best solution out there at the moment if you want an office suite that matches Microsoft Word, Excel and PowerPoint, feature-for-feature. It works very similarly (practically copying MS Office word-for-word in places) and document compatibility is near-perfect. I live in spreadsheets for my day job and WPS Spreadsheets is the best replacement I have found for Excel, bar none. Be mindful that it is closed source, Chinese-made software, and the Linux version doesn't appear to be very well maintained. At some point I'd like to do research into whether it is phoning home as some people have speculated.
- OnlyOffice Desktop Editors is a close second that is being developed rapidly and has excellent compatibility with MS Office formats, though not as good as WPS in my experience. It's quickly improving, though, and it's open source.
- SoftMaker Office and FreeOffice seem to work pretty well and have decent compatibility.
- LibreOffice is a mature and well-rounded office suite, and it is the only one of this list that has its own answer to Microsoft Access. It's not cross-compatible with Access though, so keep that in mind.
I can probably give better recommendations if you'd like to tell us about what kind of work you do the most often with Office?