is there a way to remote access from one iMac to another iMac?

I assume these are both connected to the same network.

Open 'Apple menu > System Preferences - Click Sharing'

Enable the 'Remote management' service and highlight the line to view it's settings.

Click the options button, enable everything (tip: hold alt & click one checkbox to enable all items).

Click OK

Go over to the other iMac, open a Finder Window make sure you can see the Sidebar (or look in the View menu), under the 'SHARED' section of the sidebar there shold be the other iMac, select it & click the Share screen button.

This shows the other Mac in the Sidebar & the password dialog…

Enter a username & password for a user on the original iMac.

Screensharing will load the connection in a few seconds.

Good luck