How to make a Triangular Based Pyramid ?

First, we make a 3D sketch on top plane

then, add the construction line to build the pyramid

delete the leg's dimension, change to angular dimension
the angle will be given automatically
copy the angle and use it on draft option in extrude command

add an extruded base on the frame

use move/copy body command to circular array the body
using move/copy body command will allow us to select a right line, even it is a construction line

make an extruded base on the hollow face
create lines by offseting the shape

final step is to change the depth of the first extruded base
we just use 2 different commands, and total 4 commands to build this pyramid