I am using Quartus Prime Pro with either the free or 30 days license. (Pretty sure it's the free one.)
I want to use the free version of ModelSim.
I do not need to synthesize anything at this time.
Do I have to have devices installed before I can use ModelSim? Or is there a way to just use the simulator?
I always install devices so I'm not 100% sure, but ModelSim Intel FPGA edition is a separate option in the Quartus installation (and is available as a standalone download from the download center), so you should be able to run it independently.