You can certainly install a toilet with multiple wax rings, in fact sometimes it is necessary to make sure you don’t have a leak.
The most common case is when a homeowner will install a tile floor (or really any thick floor). This effectively raises the height of the floor and increases the distance from the toilet flange to the base of the toilet. If you use a regular sized wax ring to fill in this space, it may not be large enough and as the waste is flushed, some of it may end up on your floor.
You can buy an extra-thick wax ring, or you can just buy two rings and stack one on top of the other. I would buy the type that has the rubber insert in it as it directs the waste down the hole.
Once you stack the wax rings, line up the bolt holes and push the toilet down towards the floor. The most important part is that you should feel resistance as the wax rings fill the void between the underside of the bowl to the top of the toilet flange in the floor. If you don’t feel this, it may mean that there is still a gap, which could lead to a leak.
Once you feel the resistance, put your full weight on the toilet until it comes to rest on the floor. Then you can tighten the nuts on the bolts.