Yes, you can certainly use multiple layers of epoxy for most projects. In fact, some people prefer to do it this way. If you are using a product that is a little thinner, you may be forced to do things this way. In particular, it is a good idea to do thin coats when working on a vertical surface. Thick coats will tend to run, so a large number of thin coats is your only real option.
Of course, there are certain things to remember when using an epoxy product in this way. First of all, you need to make sure that you wait for the full curing time with each layer. There is a difference between drying time and curing time, so make sure you understand that. Even when that epoxy seems to be hardened, you must not apply the next layer until the entire curing time has elapsed. You may also have to apply the heat gun on each layer to avoid bubbling.