Anything is possible. But playing in two different modes at the same time will likely mean that you are using two different diatonic scales at the same time. That's basically what we call polytonality. You might want to look up and listen to some polytonal music.
Can you have 2 modes in a data set?
A set of numbers can have more than one mode (this is known as bimodal if there are two modes) if there are multiple numbers that occur with equal frequency, and more times than the others in the set.
Can you mix modes?
You can freely mix them if you want to, improvise, play around with them and enjoy them, forget about some idea they are derived from major. That's just a coincidence. It might be good to know they use the same notes, but THEY ARE NOT THE SAME THING. They have a character all their own, modes.
Can there be 3 modes?
There can be more than one mode in a list or set of numbers. Look at this list of numbers: 1, 1, 1, 3, 3, 3. In this list there are two modes, because both 1 and 3 are repeated same number of times. On the other hand, sometimes there is no mode at all.