Transferring data to new iMac

How to move your content to a new Mac - Apple Support

It is very simple, take the Time Machine backup External Hard Disk from the older Mac and connect it to the new Mac using a USB cable. Then launch Migration Assistant (Applications - Utilities - Migration Assistant) and follow the on-screen prompts. Why this method, simple it works 100% of the time and it's dead reliable and it is fast. Any other method is prone to failures. NEVER EVER attempt a migration using Wi-Fi, it will take weeks (no I am not kidding) and will fail 100% of the time.

What about them, they will migrate over too. If you are migrating to Catalina remember ONLY 64 bit apps will transfer, so if you have 32 bit apps that you want migrated then you need to upgrade them prior to beginning your migration.

Note: Some apps such as Adobe & Microsoft apps will need to be manually installed as those developers are VERY finicky about allowing migrations.

You are WAY overthinking the process. Simply follow the directions already provided and your apps, data, settings etc. will migrate. The only thing that will not migrate is the old OS. It works 100% of the time if your follow the directions I have already provided. Millions have gone before you with zero issues, including myself on many many Macs.

Of course check your backup first to ensure the External Hard Disk is in good shape, if the External Hard Disk isn't working okay then the migration will not work either.

If the only items you want to move are on the Desktop, you can just drag and drop.

I could be mistaken but I believe the OP meant "old desktop" computer. 😎

Aha! I think you are right.