First part

Once you have a constrained sketch, turn it into a solid with a feature.

• Extrude — push a sketch along a direction to make a solid.
• Revolve — spin a sketch around an axis.
• Fillet / chamfer — round or bevel edges of an existing solid.
• Boolean — union, subtract, or intersect solids.

Each feature you add appears in the feature tree. Reordering or editing an earlier feature rebuilds everything downstream of it, since geometry is always regenerated from parameters rather than stored as a frozen shape. See Determinism on the home page for why that matters for long-lived parts.