I am brand new.
I bought a 2560 and am worried that it will have some limitations, perhaps in servo, hc05????
Should I return it?
What sort of limitations?
Yes of course it has limitations, everything does. For example it can only directly control 48 servos using the standard method. But you can get more than that in various ways if you really need to.
You're going to need to be a lot more definite about what you want to do with a Mega2560 if you want any sensible answers. Generally it can do at least as much as most Arduinos can but what do YOU need of it?
Steve