If you don't have a pen-drive you will need to burn a cd/dvd and then install it from there. It's best to start with either Ubuntu or Mint, most systems should be able to run either with no problems. Which laptop of desktop system do you have?
I want to install Ubuntu on my laptop that doesn't have a CD-ROM drive and I have no spare USB disk. I've tried Wubi, but that doesn't seem to work (since it prompts me to have the CD in the drive,...
askubuntu.com
Though I'd try it with Balena Etcher instead of Unetbootin.
If you don't have a pen-drive you will need to burn a cd/dvd and then install it from there. It's best to start with either Ubuntu or Mint, most systems should be able to run either with no problems. Which laptop of desktop system do you have?