First attach monitor, keyboard, mouse to the machine.

https://ubuntu.com/download/server

(in Mac)
Download the image file from the above link: ubuntu-24.04.1-live-server-amd64.iso

https://ubuntu.com/tutorials/create-a-usb-stick-on-ubuntu#1-overview

(in mac)
Make the installation USB stick.
The stick may contain old version ISO or others. It doesn't matter.
At first I followed the guide of the above page. But an error occurs: the image file is not gzip format.

So I changed the guides as follows:

$ diskutil list

Check where the stick is mounted at.

$ diskutil unmountDisk /dev/disk5

$ sudo dd if=~/Downloads/ubuntu-22.04.3-live-server-amd64.iso of=/dev/disk5 bs=32m

It takes, for example 1600 seconds. Now unmount.

$ diskutil unmountDisk /dev/disk5

Now insert the USB stick into the machine, turn on the machine, and go into BIOS setting during booting by F2 or DEL (for ASUS board).

Click "boot menu" and select USB stick.

Grub menu (?) appears. Select "Try or install ubuntu".

The installation starts.

Select default options, except for:

- select: update installer

- storage configuration: target disk where the Ubuntu is to be installed.
Selecting the disk, make it clear the target is what you want.

Default storage configuration is: within the disk, new 100GB partition is made and mounted as /
=> select it and edit => make the size max.

- enable OpenSSH

- enable WiFi: select the WiFi among near WiFis and insert password


After install is done, select "Reboot Now".
The message to remove the USB stick and enter.

After reboot:
$ sudo apt update
$ sudo apt upgrade