I have installed Ubuntu 16.04 (it also says LTS(if that's relevant)) from a bootable USB which my brother gave to me. He had both 16 and 18 but said that my laptop may not be able to run the 18th. Now, I want a better version, so he said I must convert it into Lubuntu. How to do that?
Keep in mind that I have a fully installed Ubuntu 16, with an Intel Atom chip ie. 1.66GHz x 2. I want to install the latest version of Lubuntu (18.10 at this time).
But, I can't spare to download lubuntu due to mobile data cap, so is there a way through which I could convert my Ubuntu into Lubuntu (without internet)?
I'm specifically looking for procedures and commands. Thanks.