Why I am unable to assign an iterator with vector index values?

Sample code

std::vector<int> testvectr;
std::vector<int>::iterator it;
testvectr.push_back(10);
it = testvectr.begin(); // method 1 - works 
it = &(testvectr[0]); //  method 2  - errors as  binary '=': no operator found which takes a right-hand operand of type '_Ty *'

Why its throwing error? I am trying to assign a vector index. So later I can call it by *it. But I didn't understand the error behind it. Pls help.