First find angle 1
You are told angle 4 = 124°, and since angles one is right beside it you know they must together equal 180° (that is because the ‘angle’ that makes a flat line is 180°, also called a straight angle, I will attach a picture)
180°-124°= 56°
Now that you know angle 1, you know all angles in a triangle must equal 180
Therefore, 58° + 56° + angle 2 = 180°
So (rewrite that equation to find angle 2 )
180- 56°-58° = angle 2
Angle 2 = 66°