How to submit fillable pdf?

My next problem is how to submit the fillable pdf - it doesn’t work with Preview on an iMac and the rcommended Acrobat reader doesn’t seem to be available in the appstore.

You can install the Adobe Acrobat Reader on your iMac by following this link: https://get.adobe.com/reader/

Here's a guide that can help: https://helpx.adobe.com/acrobat/kb/install-reader-x-mac-os.html

Let us know if you need further assistance.
Regards.