Question

what is democracy ? and what is political institution

Answer 1

a system of government by the whole population or all the eligible members of a state, typically through elected representatives.
Political institutions are organizations which create, enforce and apply laws. They often mediate conflict, make (governmental) policy on the economy and social systems and otherwise provide representation for the populous.

Answer 2

democracy is the form of govt . in which government are choosen by the peoples.
and political institutions are the procedure of regulating the conduct of political life.