Process canvas in a Windows Forms application

Question

I want to create a level editor using a Windows Forms application.

Here is the layout I want to achieve:

BLUE → Manage Windows Form

PURPLE -> Canvas, it is handled differently (yes, Windows formats also control, but not for the same use)

I have a problem though, how to make a canvas correctly without using a thread?

(Look at my other topic here: Access object from another thread )

I was thinking about a timer, but I don't know if it is reliable.

Ideally, the stream will be nice, but Windows doesn't like that you want to interact between the stream, so it messed up to be polite.

If you know how to achieve this, well, thanks! :)