I don't know your situation, budget or climate conditions, so I can say something general about the merits of some materials. I'm completely unfamiliar with metal and plastic net.
Glass is heavy (needs rigid support), difficult to fit and work with (especially on the roof), and subject to breakage, so I'd rate it low on the do-it-yourself scale, unless you have experience, or a source of cheap used windows (It's what we used at first.)
Plastic film is all right, can last several years, if you get a good, heavy grade in rolls - and if it's not exposed to strong wind. I would do a double layer, outside the frame and inside. You have to make sure it's well battened down on the outside, perhaps with strips flexible plastic strip.
Easiest of the materials I know is corrugated plastic panels ,like this
https://www.ana-white.com/wood...
We have used it for roofing and it holds up quite well to Canadian weather, without losing transparency.
For better informed advice, scroll down the list of forums to the one on greenhouses. There are a couple of real experts there.
