Help with surface separation

Hi.

Newbie question:   how can I split the two intersecting surfaces and use them as separate entities?   I need them as base for my future design, as solid bodies.

This is just an example to learn how to do it, the truncated cone won't be just that but will have an ogival shape which is harder to replicate to do a cut through a solid body (reason I am using surfaces).

Thank you.

SolidworksSurfacing