lsmod – to view modules already installed, remove old ones with rmmod
e.g. 88x2bu 2609152 0
r8168 548864 0

lspci – to check Realtek driver capability
e.g. bill@DEEPIN-Bill:~$ lspci | grep Realtek
02:00.0 Ethernet controller: Realtek Semiconductor Co., Ltd. RTL8111/8168/8411 PCI Express Gigabit Ethernet Controller (rev 10)

sudo apt-get update
sudo apt-get install build-essential dkms git
git clone https://github.com/cilynx/rtl88x2bu
cd rtl88x2bu/
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

Deepin Linux 20.1:

sudo iwconfig INTERFACE essid AP_ID key s:PASSWORD

sudo apt update
sudo apt -y install dkms git bc
git clone https://github.com/fastoe/RTL8812BU.git
cd RTL8812BU
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
sudo reboot