Connect the drive to your Mac via USB. If your Mac only has USB-C ports and your drive has USB-A, you’ll need a dongle or adapter (consider buying a USB-C to USB-C Seagate drive if you want to avoid this).
Open Finder . You should see the drive appear on the left sidebar under "Locations." Click it. If you can drag a file onto it and it fails, you’re in read-only mode.
If you need to share the drive between a Mac and a PC, do not format it as APFS. Instead, use exFAT in Disk Utility (same steps, just choose "exFAT" as the format). It works on both systems but is slightly less robust for Time Machine backups. Bottom line: Buy the Seagate, spend 2 minutes reformatting it, and enjoy reliable, high-capacity storage for your Mac at a fraction of the price of "Mac-specific" drives.
Reformatting erases everything . If there’s pre-loaded software (like Seagate Toolkit) or sample files, copy them to your Mac first, or just download the Toolkit software later from Seagate’s website.
