Is it possible to have 2 CPU?

I don't think so, there is only one socket

yes its very possible but I dont see a point because you'd be gettinf more use out of your pc if you bought more cores

It depends. You need a motherboard designed for two CPUs. And while it does make the machine "faster" there are some tasks that can't be distributed across multiple CPUs or even cores. So those tasks are always going to be bottlenecks to your speed.

It is possible to have two CPUs, in fact, most professional level servers have dual CPUs. I personally own a Dell PowerEdge 1950 and mine has two CPUs, with one on each corner of the motherboard. This is actually really common for servers in order to balance the load.