Using Standard Code:
1. You need a class to tell the turlte, aka the pen, direction, color, steps, etc.
2. You need a console menu that can input direction, steps, color, etc
3. You need to draw the turtle using a specific character like '@'. Instead of dynamically outputting the characters to the console output, you should use a matrix to define the "canvas". Then you can just print the matrix. This illiminates display problems and gives your tutle a working region. Be sure to prevent out of index problems with your matrix.
Using The Windows Api:
1. You need a class to tell the turlte, aka the pen, direction, color, steps, etc.
2. You need a windows API implementation of an editable client area that supports user input for direction, steps, color, etc.
3. You need to create a buffered BMP file in memory then draw the turtles action to that buffer. When you are done drawing on the buffer BitBlt the BMP resource to a client region (if you are using a resource script this should already be defined in the rc file).
Wasn't sure if you wanted to actually draw graphics or to just print letters on a console window, so I gave you a short how-to in both.