What is oxidising agent and reducing agent explain with examples . Please explain me so that I can solve any question regarding it

An oxidizing agent is a substance that oxidizes other chemical substance and reduces itself. Oxidising agents give oxygen to or removes hydrogen from other substances.

The reducing agent undergoes loss of electrons. A reducing agent (also called a reductant or reducer) is an element or compound that loses (or "donates") an electron to another chemical species in a redox chemical reaction. Since the reducing agent is losing electrons, it is said to have been oxidized.

eg:3MnO2+4Al→3Mn+2Al2O3

Reducing agent: Al

Oxidation Agent: MnO2