If the iPod is currently set to sync to the old MacBook, it will not sync automatically to the new MacBook, unless you change that association. iPods can only use automatic syncing with one iTunes library at a time, because sync ("synchronize") means iTunes is keeping the iPod the same as one iTunes library (or a portion of that library that you select).
You can set the iPod to automatically sync with the iTunes library on the new MacBook. In the process, the iPod is erased and content from the new MacBook's iTunes library is synced to iPod.
OR, you can transfer your complete iTunes library from the old MacBook to the new MacBook. Then, iTunes on the new MacBook looks like iTunes on the old MacBook (except for changes related to iTunes versions) with ALL of your songs (and other media) plus supporting data, such as playlists, play count, ratings, date added, etc. Your iPod also sees the iTunes library (on new MacBook) as the same iTunes library (on old MacBook), because it IS the same iTunes library.
I think transferring the complete iTunes library is better... This document describes the procedure to back up your iTunes library to an external drive.
Back up your iTunes library by copying it to an external drive - Apple Support
The first step "consolidates" your iTunes data into the iTunes folder, which is located in your user account Music folder. For a Mac user, if you use the default settings in iTunes, all of your iTunes data should already be in the iTunes folder, but it does not hurt to do this step. The second step copies that iTunes folder to an external drive. The third step restores the iTunes folder backup from external drive; in your case, you "restore" (copy) it to the new Mac to replace the existing iTunes folder that is there. Do this with iTunes NOT running. Since you added new songs to that new iTunes folder, you should not delete it; move it to a new location, like the Desktop. Then copy the iTunes folder from the external drive in its place. When you run iTunes on the new MacBook, it uses that iTunes folder, which has your iTunes data from the old MacBook.
NOTE: You don't have to use an external drive, if you can set up File Sharing between the two MacBooks. You can do the second and third steps in one shot by copying the iTunes folder directly from old MacBook to new MacBook.
After you confirm everything looks good in your (restored) iTunes library, you can manually add anything that is not there from the iTunes folder you moved to the Desktop.