Is circles necessary for conic section?

I'm having a jee mains pattern test in 4 days, in maths parabola and ellipse are coming and I have not completed circles( like I have basic knowledge eqn of circles, position of point ect) and I will be watching one shot of nv sir for parabola and ellipse so Is it necessary to watch one shot of circles to complete parabola and the whole comic section because I don't have much time I have to do the parabola to a good level(like full allen module)