I am a very basic user in Illustrator, attempting to use the Object > Envelope Distort > Make with Top Object function. The two objects are 1)text, and 2) a graphic that I did not use the pen tool to create.
I am receiving an error that "the top object must be a single path or mesh". How do I convert my graphic to a single path object?
It's exactly what it says. You have to have a single, closed path.
You cannot have a compound path neither a photograph (that's not a path) to distort your object.
A single path, by definition is a path that does not contain multiple paths. (Now that's what I call a definition! Hehehe... :-) A compound path by definition is a path that contain multiple paths combined into a single path. For example you take a big circle and place a small circle inside of it so that they don't touch. Now you make this into a "single" path by Object > Compound Path > Make. This would be a compound path. You cannot use such a shape for distortion. Another example would be a letter 'b'. The inside of it is hollow. So it has an outer path and an inner circle/oval (so these two make a compound path) and in-between these two paths are colored black.
For example, to make a single path, take a pencil, put it down on a piece of paper, and draw a path without:
a. lifting your pencil and
b. crossing the pencil lines you already made.
And finally, close your path by moving the end of the line where you started. Now your path is closed (the ends meet) and the lines don't cross each other.
In AI, in order to qualify as a closed path, the endpoints must actually be welded/joined. In other words, you cannot just move the end anchor point to the top of the beginning anchor point. They must be welded or joined.
Examples for BASIC closed paths are circle, ellipse, triangle, rectangle, star, polygon. Of course you can draw any type of closed paths using the pen tool as long as the lines are not crossed and the end point is joined to the start point.