I don’t think that will help you, unless your main B-1300 is already located in a sub-optimal location in your apartment. You should start with placing your main B1300 in a location for optimal reception from the school’s wireless network. You can test this by running speedtest.net or similar from a computer connected by ethernet (using the LAN port of the B1300). Once you find the location for your main B1300, now the issue is trying to connect a second B1300 to improve the signal to locations far from the main B1300.

You can treat the LAN port of your main B1300 as essentially your own, private Ethernet port. At that point, if you can run a long Ethernet from there to the far side of the apartment (or at least as far as you can), you can set up any AP there you want. If that second AP fixes your problem, you are done.

Alternatively, you can try to just set up the second B1300 as a WDS repeater. I haven’t tried it (creating a WDS repeater to repeat a WISP repeater), but my hunch is that it would work. I could try it at some point and let you know, but it won’t be for a few days at the earliest.

Another option would be to forgo the second B1300 and purchase a matched pair of mini GL-Inet routers. You could hang one off the LAN side of your main B1300 and set up a WDS pair.

But, whenever possible, use wires instead of wireless. Let me know how far you can run Ethernet from your main B1300 as described above.