What is angle of incidence? and what us angle of reflection?

Dear student,

Here, the incident ray (red), the reflecting surface (blue), the surface normal (black) and the reflected ray (green) are clearly shown.

The angle of incidence (i) and angle of reflection (r) are also shown keeps the normal as a reference.

so, by definition

Angle of incidence (i) is the angle made by the incident ray (red) as it hits the reflecting surface (blue) with the normal to the surface (black).

and

Angle of reflection (r) is the angle made by the reflected ray (green) as it originates from the reflecting surface (blue) with the normal to the surface (black).

Now, from the laws of reflection, we know, 

that angle or incidence = angle of reflection.

so,

angle i = angle r
Regards