Oh it's even stupider than that.
In most cases it's, A. Just a link which happens to be a jpg. Which means it the website wants to change the jpg they can or if the website goes down it points nowhere.
Or B. Just a hash, which might supposed to be a unique representation of a specific image, but really is just a string of characters, so different sites might disagree what that image is.
The ".com" and ".org" and all other Top Level Domains are owned/controlled by some organization.
Com and org are your original TLDs, so since they were around first you see them everywhere. At some point countries got their own TLDs so Mali got "ml" for example but Tuvalu got "tv". (Yes, technically ".tv" has nothing to do with television.) And a few years back there was open bidding for a bunch of new TLDs which is where ".sport" or ".dentist" come from.
Anyone some entity owns/controls them and then can sell any word or domain under it. So if you want "greatgatsby.com" you have to talk to the ".com" owners. If you want "greatgatsby.sport" you talk to the ".sport" owners. Usually there is another company or agreement that groups these together so you can manage all your domains in one place.
So anyways now you own a domain like "greatgatsby.sport", what do you want to host? Mail at "mail.greatgatsby.sport"? A website at world wide web aka "www.greatgatsby.sport"? Up to you.
Over time, largely by convention "www" became where you put your website.
From there you have two options, you can setup a redirect from "http://greatgatsby.sport" to "http://www.greatgatsby.sport" or you can do a little hosting "trick" and just make "http://greatgatsby.sport" return your website.
I've been playing on "console" (SteamDeck) so I know the UI is different but the issue I've found is that there are three different "inventory" options and two different "loot" options, and each behaves a little differently.
For example if I loot a corpse, you're right I can send to a specific party member. However if I loot a chest, that has to go to me.
Similarly when I the character sheet inventory view I can sort by certain methods and then L3(?) to exit that menu. If I'm selling something it's still (L3?) to open that menu, but B to exit it. Also the sorting options aren't the same. Also switching between characters during a trade event is one button. However switching on the character sheet is three buttons. There is also a third lesser used "put in device" menu with even fewer sorting options and you can't switch characters.
The game is excellent and you can get used to these things but I do sometimes have to spend time just sorting things.