Yes Modelsim is other product with other license.
see https://www.intel.com/content/www/us/en/software/programmable/quartus-prime/model-sim.html for more details.
The ModelSim-Intel FPGA Starter edition is included with a license. If you want to use the full ModelSim-Intel FPGA edition, it is an additional license.
For more complete information about compiler optimizations, see our Optimization Notice.