i believe Nvidia quadro cards can use vGPU without licensing, theres also ways to use GTX 10 / RTX 20 cards with an unlock and by emulating their vGPU profiles as quadro cards to avoid licensing. nvidia probably has the best support/documentation online for all of these things but can be the most problematic/complicated/costly if you arent profiecent and/or willing to violate their terms of use.
intel cards or iGPUs with SR-IOV / GVT-g (like the card Mir recommended ) are often great, iGPU was one of the easiest ones i've worked with. if your system has an iGPU you can actually use vGPU profiles with an iGPU (although with low vram usually so only for basic 3D and usually for a low number of instances like 1-4 depending on the iGPU/CPU that you have and the higher the number the lower vram you can assign. ) but if all you need is a few vGPU profiles, an iGPU can be all you need.