Can you just share a drive on the network?...yes...will it work properly for several stations to access it at once?...no.
You need to look into a shared storage solution.
Have you looked into qnap or like products?
Your imac can certainly get an external 10g added to it via thunderbolt. The laptop probably as well.
I use a Qnap with a 10g switch, and 10g runs to two pcs running 10 g cards, an Imac 2020 with an OWC thunderbolt to 10g connector, and an old imac with thunderbolt 2 connected to 10g via a sonnet external chasis and a 10g card inside it. The price of all the connectors add up, but that's the cost of shared storage.