How to create a boot pendrive in Ubuntu?

I am using ubuntu, but I am trying to reset it to delete things that I cannot. I do not know how to create a bootable pen drive because ubuntu does not has Rufus to create this bootable pen drive.

Ubuntu comes with a Startup Disk Creator by default.

Press the Super key (usually left windows key) and in the serach box type startup and you will be provided with options including Startup Disk Creator which you should select.

This will provide you with the following window from which you can make your selection as to the iso you wish to use (the top selection) selecting Other... if the iso is not in your /Home/[user]/Downloads directory and then Make Startup Disk by selecting the already inserted USB pen drive in your PC.

Then click on Make Startup Disk when the routine will commence.

Note that if there is already something on the USB drive, it will be overwritten by the Startup Disk Creator and there is no need to perform any other tasks on the drive before proceeding.

reference which also includes instructions which apply to making a Windows bootable USB from within ubuntu.

You can use a tool named WoeUSB. It is same as Rufus. You can make a windows or any kind of operating system you wish. All you have to do is

sudo apt install git p7zip-full python3-pip python3-wxgtk4.0 grub2-common grub-pc-bin

and then enter your sudo password, then

sudo pip3 install WoeUSB-ng

Ubuntu installs it automatically for you

More details: https://github.com/WoeUSB/WoeUSB-ng

Have a great day :)

Persistent Install vs Full install

Ubuntu can be installed to a USB in different ways. A Live install does not save between sessions. A Persistent install extracts the OS from a compressed file and saves data to an overlay file or partition each session. A Full install installs the complete OS to the USB just like an install to internal disk.

Comparison between Persistent and Full install USB

Advantages of a persistent install:

1. You can use the persistent pendrive to install Ubuntu to another computer.

2. A persistent install takes up less space on the pendrive.

3. You can reset the pendrive by overwriting the old casper-rw file with a new one.

4. The install to pendrive takes less time.

5. Slightly less wear on the drive.

Advantages of a Full install:

1. You can update and upgrade.

2. If you have problems or wish to modify, the solution is the same as with an internal install, (You can ask for help in the forums).

3. No ugly startup / install screen.

4. Better security, you can use full encryption

5. You can use proprietary drivers.

6. Swapfiles and partitions work and Hibernation can be enabled.

7. Many persistent installs are limited to a 4GB casper-rw and a 4GB home-rw persistence file, to get more persistence requires persistence partitions. Once casper-rw is full, the drive will not boot.

8. More efficient usage of disk space. Does not require reserved space for persistence.

9. Faster boot, no automatic disk checking or Try Ubuntu/Install Ubuntu screen.

10. You can run VBox and use virtual machines.

11. Generally faster boot than Live or Persistent USB's.

12. More stable, better for day to day use. I have run Ubuntu off a flash drive for 5 years making only LTS upgrades.

Note that once booted, both methods run at about the same speed. If the computer has lots of RAM Ubuntu should run mainly in RAM and there will not be a big difference between running off internal HDD and USB3 flash drive f.

Full Install Method

A quick and easy method to flash a Full install to USB can be found here: Easy Full Install USB that Boots both BIOS and UEFI

A more traditional methods for creating a Full install USB from scratch can be found here: How to Create a Full Install of Ubuntu 20.04 to USB Device Step by Step

Persistent install method

The following tools can be used to make a Persistent install USB: mkusb - https://help.ubuntu.com/community/mkusb, Rufus - https://rufus.ie/en/, Universal USB Installer - https://www.pendrivelinux.com/universal-usb-installer-easy-as-1-2-3/, Ventoy - https://www.ventoy.net/en/index.html, YUMI- https://www.pendrivelinux.com/yumi-multiboot-usb-creator/. and others.

mkusb is my favorite tool for making Persistent USB's https://help.ubuntu.com/community/mkusb. It creates boot partitions that allow it to boot in BIOS or UEFI mode. It puts the OS on a read only ISO9660 partition that is difficult to corrupt. Persistence goes on an ext4 partition who's size is only limited by USB size and it will make a NTFS data partition so you can save data from a Windows or a Linux computer