usb wifi adapter not recognized [duplicate]

So I've been experimenting with Ubuntu on and off for a while, but I honestly have no idea what the hell I'm doing. So I have a realtek RTL8812bu WiFi dongle that I'm hoping to get working. I did some research, and came across this driver on GitHub that a couple people across two threads said worked for them:

At the bottom it said there is a new version here. So somewhere it said it was confirmed to work on kernels up to 4.16, so I checked and I'm on 4.15.0. But the problem I'm having, is what am I supposed to do? There is some installation guide at the bottom that is about as clear as mud to me since I don't know much.

Almost all of the instructions are in the README on the second site you linked. I’ll fill in a few blanks.

With a working internet connection by ethernet, tethering or whatever means possible, open a terminal and do:

sudo apt-get update
sudo apt-get install build-essential dkms git
git clone https://github.com/cilynx/rtl88x2BU_WiFi_linux_v5.2.4.4_26334.20180126_COEX20171012-5044.git

Now, from the README:

cd rtl88x2BU_WiFi_linux_v5.2.4.4_25643.20171212_COEX20171012-5044
VER=$(cat ./version)
sudo rsync -rvhP ./ /usr/src/rtl88x2bu-${VER}
sudo dkms add -m rtl88x2bu -v ${VER}
sudo dkms build -m rtl88x2bu -v ${VER}
sudo dkms install -m rtl88x2bu -v ${VER}
sudo modprobe 88x2bu

Please be aware that the ‘build’ process takes a few moments; please be patient.

Your wireless should now be working.

I tried several different drivers, but the one I finally got it working was from this repo: https://github.com/morrownr/88x2bu

In short, the steps you should take are:

1. Test that your dongle actually needs RTL8812BU drivers:

   • In a terminal (Ctrl+Alt+T) run:

     lsusb
     

     This will give you something like:

     Bus 001 Device 002: ID 2357:0115
     

   • Google the ID number, e.g. "wiki 2357:0115", and you will find out which Realtek driver you need.

2. If you indeed need RTL8812BU and you are on Ubuntu 18.04, 20.04, or 20.10, run the following:

   sudo apt-get update
   sudo apt-get install -y dkms git
   mkdir src
   cd src
   git clone https://github.com/morrownr/88x2bu.git
   cd 88x2bu
   sudo ./install-driver.sh
   sudo reboot
   

You could try the next:

sudo apt-get update
sudo apt-get install build-essential dkms git
git clone https://github.com/cilynx/rtl88x2BU_WiFi_linux_v5.3.1_27678.20180430_COEX20180427-5959
cd rtl88x2BU_WiFi_linux_v5.3.1_27678.20180430_COEX20180427-5959
VER=$(sed -n 's/\PACKAGE_VERSION="\(.*\)"/\1/p' dkms.conf)
sudo rsync -rvhP ./ /usr/src/rtl88x2bu-${VER}
sudo dkms add -m rtl88x2bu -v ${VER}
sudo dkms build -m rtl88x2bu -v ${VER}
sudo dkms install -m rtl88x2bu -v ${VER}
sudo modprobe 88x2bu