This instruction video shows you how to create a simple chair model in Blender
TAB – Switch mode (from Object to Edit mode for instance)
S – Scale, S followed by Z – Scale in Z

Loop Cut Tool – Cuts a face loop exactly in half
To leave the loop cut tool, hit W for select box
Alt – LMB (Left Mouse Button): in edge selection mode (2) click on an edge to select an edge loop
X – Delete: to delete the selected edge loop, select Dissolve Edges from the menu that pops p.
E – Extrude
Bridge can be found in the Edge menu, even if you have two faces seelcted