You can't invite an accountant to QB Mac. The easiest is for your accountant to remote into your computer and work on your file.
If your accountant has QuickBooks Mac - same year as you - you can send the QB file to your accountant but you can't use your file while the accountant has it.
If your accountant doesn't have a Mac, you can save your Mac file as a Windows file and send it to your accountant. He needs to open it in QuickBooks for Windows in the same year as your Mac version. And, the accountant can send the file back to you to load into your Mac version. This is roundtripping and I wouldn't recommend doing this on a monthly basis. Only use it occasionally. Again, you can't work in your file while your accountant has the file.
Or, you can convert your Mac QB file to QuickBooks Online and both of you can easily view it.