That's where a little switch is to divert air from print bet to side
That's the glass
And that's the simple enclosure I made. Not air tight but just keeps air from blowing and keeps it warm and toasty for bigger longer prints.
And the autodesk fusion 360 is free for a hobbyist. Also has cam, cad, stress, rendering, ect. I figured if I ever go into cnc machines I will already be familiar with design software. Lots of tutorial videos on the tube for learning also. Just my opinion but I was told about the software by someone else and wish I started with that. Lots to learn but I guarantee you will never outgrow it