Below were steps that I executed on my NUC7CJYH model

Once Ubuntu 18.04 is installed on NUC with having a wired network connection, follow the below steps to enable wifi on the Intel NUC:

• sudo apt install wpasupplicant

• Update the /etc/netplan/50-cloud-init.yaml as below

network:
    ethernets:
        eno1:
            dhcp4: true
    wifis:
        wlo2:
            dhcp4: true
            access-points:
                googlewifi:
                    password: xxxxxxx
    version: 2

• sudo netplan apply

• After a couple minutes, executing ip a will display IP address having been assigned to the wireless interface

#Below is the link to create a bootable 18.04 Ubuntu on USB stick (steps on Ubuntu OS)

• https://askubuntu.com/questions/372607/how-to-create-a-bootable-ubuntu-usb-flash-drive-from-terminal

sudo apt-get install syslinux
sudo mkfs -t vfat -I /dev/sdX
isohybrid /path/to/file.iso --entry 4 --type 0x1c
dd if='/path/to/file.iso' of=/dev/sdX bs=8M
sudo -s
cat /path/to/file.iso > /dev/sdX
sync