I am making a game where the user is given a letter on screen such as the below image

The user then uses the mouse to draw from one point to another until the shape is drawn.

I wanted to know what is the best way for the program to create these points so that they appear on screen for the user to interact with them?

I have a canvas and the mouse is able to draw on the screen the problem is I don't know how to make the points interact-able with the mouse, so that when the mouse draws on or over the dots that it connects them together to form the letter.