Hey there, @FETA.
Welcome to the Community!
To properly migrate your file from QBDT MAC to QuickBooks Online, you'll need to move your QuickBooks Desktop Mac file to QuickBooks Desktop for Windows. Use the link below to change to Windows:
Move QBDT Mac file to QBDT for Windows
This is currently the only route you can take to successfully migrate your data over to QuickBooks Online.
If you have any additional questions, please let me know. I'm only a post away. Bye for now!