Fedora VS Ubuntu? What is the difference?
 

Fedora or Ubuntu and why?

A good habit to get into when using Linux is to use Google to answer questions which have already been covered in depth:

https://itsfoss.com/ubuntu-vs-fedora/
https://www.educba.com/ubuntu-vs-fedora/

The second article even has an infographic for those who don't want to read too many words and would prefer to look at pictures.

If you're still curious as to which would work for you, try both out, that's the only way you'll really know and that's why live versions exist.

If you want a bleeding-edge Linux distribution, then Fedora is the clear winner. Fedora is basically Red Hat's test-bed for the newest goodies on offer - so you'll get the most recent versions of different things. If you don't want that, pick Ubuntu (or Linux Mint for that matter).

Besides the "bleeding edge" nature of Fedora, Fedora use *.rpms and Ubuntu uses *.debs for its package management.

As jsbjsb001 said, Fedora is Red Hat Enterprise Linux's (RHEL) test bed for trying new stuff. Ubuntu is based on Debian Sid, Debian's testing distro. Despite Debian's aliasing Sid to "unstable" (their term), I have used it off and on for years and it's pretty darn stable.

I'm no Ubuntu groupie, but, between the two, I'd pick Ubuntu, but that's simply a matter of personal taste.

Presumably you're an all-around newbie, unfamiliar with the major attributes of each. Otherwise, you shouldn't need to ask the question. Assuming Fedora and Ubuntu are the only two that can be considered, then I recommend Ubuntu. Why? More stable support base. Fedora is the faster evolving of the two, so when you're looking for answers, with Fedora you're more likely to encounter the confliction of obsolete ones, while Google's heavily relied upon database is heavily biased toward Gnu/Linux answers found on Ubuntu's websites. If you're more independent and/or industrious and/or self-sufficient, then probably you want to lean to the faster evolver, Fedora. If stability is your leaning, then choose Ubuntu LTS. Non-LTS Ubuntu releases lag Fedora not so much.

If you're still not sure which is for you, try each for several months or more, and pick the one to stick with based upon how well their support systems, installer, package management and update systems fit you. This goes for any distro, not just these two. Most of the major distros supply most or all of the same desktops, which can be added or changed without changing distros. Most application software is agnostic, and available regardless of distro.

FWIW, neither has ever been #1 in a recommendation list I created, in very large part because of the character of the Gnome desktop that is their default.