https://askubuntu.com/questions/1071299/how-to-install-wi-fi-driver-for-realtek-rtl8821ce-on-ubuntu-18-04
Ok here goes:
1. Open a terminal.
2.
sudo apt-get install --reinstall git dkms build-essential linux-headers-$(uname -r)
3.
git clone https://github.com/tomaspinho/rtl8821ce
4.
cd rtl8821ce
5.
chmod +x dkms-install.sh
6.
chmod +x dkms-remove.sh
7.
sudo ./dkms-install.sh
8. Reboot your PC and walla! your wifi should be working. Insya Allah.