Is the only way to install linux with a bootable usb?

Hello nerds of linux, I am trying to install linux onto my laptop that I've recently gotten from my grandpa and I don't feel like buying a usb. Is there any way I can use something else to install linux or would I need to buy a flash drive? I'm honestly hoping I could just use my phone somehow but after doing some research it doesn't seem like thats an applicable option.