No wifi adapter found - Lenovo Ideapad S145 - 20.04 Ubuntu

I bought new Lenovo laptop and installed Ubuntu 20.04 through USB.

While setup screen it did not asked for Wifi and the third party checkbox was disabled, it could not be selected.

When installation was finished, it showed "No wifi adapter found" when trying to connect. I can connect to Internet through mobile phone tethering.

This is value when entering rfkill list all in terminal: Screenshot

0: ideapad_wlan: Wireless LAN
    Soft blocked: no
    Hard blocked: no
1: ideapad_bluetooth: Bluetooth
    Soft blocked: yes
    Hard blocked: no
2: hci0: Bluetooth
    Soft blocked: yes
    Hard blocked: no

I tried this solution, but it said: error focal release not found.

What should I do so Wifi can work? Thank anyone for help.

edit Screenshot of lspci -nnk | grep -iA3 net:

edit Screenshot after: sudo apt-get install rtl8821ce-dkms

It seems that install went ok, but still Wifi is not enabled. Tried to restart laptop and still adapter not found.

Solution 1:

Reboot in the BOIS/UEFI and make sure that secure boot is off. You might have to set an administrator password for this.

Press F10 or F12 to save and exit

Once the machine has booted into Ubuntu, establish a temporary ethernet connection by plugging your cellphone into the USB port and settings >>> connections >>>> mobile hotspot and tethering >>> USB tethering.

Open a terminal.

Paste this line into the terminal :

sudo apt-get install rtl8821ce-dkms

Press Enter

Reboot your computer. Your WiFi card should work now.