Converting WPA2-Enterprise to WPA-Personal on AR300M?

I recently bought AR300M to converting WPA2-Enterprise (in my dorm) to WPA-Personal. However, when I am using WISP mode, it is not giving an option to connect WPA2-enterprise. After doing some research, I found out that I need to upload the firmware. I have download the firmware from here

but I am not able to upgrade it. I tried through web UI but it is uploading and I don’t know how to do it via root. I am a newbie in this area. Can someone help me with specific direction on how can connect to WPA2-enterprise? Thanks.

When you choose SSID with WPA2-Enterprise, it should give you a box to enter username and password. Doesn’t the factory firmware work this way?

Actually I am not trying to set up WPA2-enterprise. I want to set up a WPA-PSK but the current available network in my dorm is WPA-enterprise. So I am not able to convert it to WPA-PSK using this router.

AR300M’s firmware can be store in both nor or nand. by default nand. the only privide a nor one.
You can flash nor firmware by uboot web, please refer to this.
After flashing nor firmware, the system will still boot from nand, you need extra step to let it boot from nor, please check: