I need some help here.

My iMac HD died. It was a 2 TB unit. I had Time Machine running on an external HD and have a good back up.

I just got my new replacement Mac but its HD is only 1TB. Adding to the problem my old HD is OS Mojave. The new computer is Big Sur.

What should I expect with the above reality?

Can't you just restore what you need?

is that possible using the Time Machine back up?

https://www.imore.com/how-recover-files-your-old-mac-without-having-migrate-your-entire-time-machine-backup

well damn.

I thought you had to do the entire thing in one shot.

Thank you for the help.

Grab the Samsung T-whatever they're up to now 1 or 2 TB external and do the rest. Or, get a dock and install a 2TB SSD, hooked into the iMac permanently.

Yeah, storage is a big issue on Macs when changing computers as they're hard drives and memory on the machines are so expensive. I try to keep as little as possible on the actual machine drive.