The work of the FResultHit structure

Hello! I’m trying to get a normal vector from the surface that the sphere hits. I decided to do this via FResultHit resultHit.Normal, but I don’t fully understand how this structure gets collision information. Is it independent and receives all the information about it in a collision, or does it need to be passed as a parameter to get information about the collision? If I do so:
FHitResult hitResult;
FVector vector=hitResult.Normal; will I get information about the normal vector, or will nothing happen and I need to pass hitResult, for example, to SweepSingleByChanel()?