Does Blender have the equivalent of Photoshop Smart Guides? I'm doing my first blender tutorial. I want to extrude a face to create an upper lip but I don't want it to be larger than the lower lip as I extrude. In photoshop this is easy because the smart guides automatically create a pink line when and object you're dragging or extruding aligns with another edge/object.

Example:



I tried the solution found here: Object alignment/Pattern Object/Smart Guides in Blender but that did not actually apply to my use case at all.

I tried the different snap options but none of them seem to do it. If not, what's a simple way to guarantee that an extrusion does not go beyond a certain point?
"Snap" is what you're looking for, but the way to use it isn't really intuitive if you come from Photoshop. Please let me detail the procedure step by step.

Starting with the default config :


Set the "Snap element" to Vertex
Start to extrude with E. If needed, specify an axis (X in your case)
Keep Ctrl pressed, and move your mouse cursor to either A or B. When the face snaps, press left mouse button to validate.