Parliament has one power. It can pass motions.
These motions can become Acts of Parliament and define new laws. The text of the Act of Parliament is basically unlimited. An Act of Parliament can, in theory, consist of nothing but the word "Rhubarb" written 5000 times. It could contain a statement that "pi = 4", or it could repeal the law of Gravity. These are silly examples, but they show that Parliament can create any act that it chooses. How that relates to "power" is more questionable.
Obviously, an Act that declares "pi = 4" would have no effect on the actual value of pi. Similarly an Act that is unenforceable, will not be enforced.
Could Parliament change the electoral system to vary who gets to vote? Yes they have done this multiple times in the past. The direction of history has meant that the franchise has been extended each time, to include non-property-owning men, and then to include some women. But it is far from the case that "everybody" can vote. Prisoners, under-18s, and The Queen, for example, have no vote in elections. Parliament could make it impossible for women to vote, but such a law would be unenforceable.
The ultimate check on the power of any authority is the risk of violent revolution. This restriction on the power of any government is implicit.