I suggest u go through properties of line, circle, conics and 3D ones thoroughly via R.D.Sharma objective maths or any book u like [but i prefer R.D.S.]. start practicing those solved examples without seeing the solutions because there are some more helpful properties u will find in those examples.
the main situation comes with usage of 3 diff. eqn i.e. point form, slope form, and parametric form in tangents and normals sums. u need to carefully understand which eqn shd be used or which cd be less time consuming.