Hello, xpaddy01. I think I'm excited for you also. 🙂
The Mac mini is perfectly capable of acting as the server for network data storage for both laptops.
You will, of course, need to buy an external drive that has enough capacity to comfortably house all the data that you expect to produce. Video files especially can be very large, and for the music app it's the sound and sample libraries that consume the greatest storage.
Yes, you will connect the network drive to the mini and share it on your local network. It isn't very difficult at all to do. Once done it's rather self-sufficient.
From a musician perspective you'll want to maintain Logic's sample library and ancillary files on the laptop itself, or on an external drive that can travel with it so that the app always has what is required for music production. Copies of the library can be kept on the network drive along with project files and finished recordings. I don't do FCP, but I'm sure there will be a similar requirement for FCP project files. An external drive for that laptop may be useful.
Also consider that you must backup all of these devices and drives. Each laptop will require a backup drive of sufficient capacity to backup the total storage of the internal and potentially the external drive as well. A rule of thumb for backup drive capacity is 2-3x the total capacity of the drive(s) being backed up by that computer. There will be files on each laptop that will be held separately from the network drive, that's why you'll back them up individually.
You will want to provide backup of the network drive, too, so figure another large external drive that the Mac mini can use for that. Again, 2-3x the capacity of the mini's internal drive + the network drive.
Time Machine is a good backup solution for the Mac. The software is already included on the Mac and once setup usually runs pretty flawlessly There are other options such as Carbon Copy Cloner and SuperDuper! among others.
A great source for external drives, accessories and guidance is OWC/macsales.com. They know their Macs and have a very supportive and knowledgable crew. Many veterans of the community swear by them, as do I.
I wish you luck🍀 as you move forward with your upgrades and I'll be following the thread.
