Build the stepped bar
The three views below show one part. Build it: start from the full block the views enclose and remove material until your part matches all three. Count grid squares to read each size, and check every feature against more than one view before you cut it.
The part, in three views
corner 1 of 4
Click a face to cut that block away. Right-click to put a block back. Use Turn left/right to walk around the part: a feature on the far side cannot be reached from here.