Can these windows be shuttered from light in a simple and efficient way?
(That window type is called jalousie or louver windows, by the way.)
If you search for &quot;jalousie window seal&quot;, you'll get some products that come in a roll and assist in sealing the gap between each window. That should help with the airtightness, though not as much as a real window would.
You could also use an &quot;interior storm window&quot;/&quot;storm window insert&quot;, which is basically a sheet of plexiglass with a seal around the outside, designed to fit snugly in the window. This is a somewhat expensive and bulky solution, but would actually seal the window. Up to you if $100+ is worth it for something that you'd leave with the apartment after a year. (It's also possible to hand-make something like this. The tricky part is the seal.)
For light blocking, I would suggest paired command adhesive hooks, (the bigger ones) and stringing a curtain rod between them. Looking at the blinds on my patio door, which use a similar design, you should be able to squeeze a curtain between the blinds and the wall, though you'd need to do the curtains as a pair because of the support in the middle. If you can't fit the curtains back there, go over the top; place the hooks as far up the wall as you can (remember that the hooks need a bit of room above them) then just drape them over the blinds. Looks ugly, but it works; had the same setup growing up.
If that's not working out well, my backup recommendation would be a four-poster bed. Instead of using blackout curtains on the actual window, you get a four-poster bedframe, and just hang heavy fabric off of that instead.
jalousie window seal: first Google shopping result. Not a recommendation, I haven't used this or researched this product that well. Note that this goes over the edge of each glass pane, fitting between that pane and the next. It's sold as a roll, and is cut to length. You can buy this from multiple sources, but I suspect they're all pulling from the same factory.
Interior storm window site: first Google result. Not a recommendation. Here, you have choices. You can roll your own with a trip to the hardware store (plexiglass, cutter, and something for the edges), get a kit (you still buy the plexiglass locally, but the other stuff gets shipped), or buy premade online. All these options are kind of expensive.
Command Adhesive This actually is a product recommendation. Command Adhesive is what I've used in all the places I've rented to hang curtains in my bedroom. It's designed to hold, and be removed without damage. I'm recommending the brushed nickel hook as it looks a bit better than the plastic ones, and the 5lb one because there's a possibility that you'll need to put it over top of the existing blinds, and Command Adhesive is weakest at withstanding pulling.
Four-poster bed: selected because it's less horrifically expensive compared to some of the other options. Not a product recommendation.