Using the diagram below, doing the folds in order gets you a rectangle.

If we must treat the two protrusions on the left side as separate objects, simply moving fold $1$ to the left fixes. The point of this is to see a rectangle inside of the shape, everything else follows basically immediately.

This just need 4

When will the results be published?

By a fold of a polygon-shaped paper, we mean drawing a segment on the paper and folding the paper along that. Suppose that a paper with the following figure is given. We cut the paper along the boundary of the shaded region to get a polygon-shaped paper. Start with this shaded polygon and make a rectangle-shaped paper from it with at most 5 number of folds. Describe your solution by introducing the folding lines and drawing the shape after each fold on your solution sheet. (Note that the folding lines do not have to coincide with the grid lines of the shape.) Proposed by Mahdi Etesamifard