将一个正方形从起点移动到以固定速度点击鼠标的位置

I'm trying to move a square from it's original position to the coordinates of my mouse when I click. The code I have somewhat works, but the square does not go directly to the mouse click. It goes diagonally a bit off, then it goes to the mouse click, as shown in the picture. I tried to make it a straight movement path but I could not think of a way to do so. I'm pretty sure the error is something to do with the 1st method below.I'm trying to move a square from it's original