Answering questions sounds fun. For reference though, I don't do a lot of worldbuilding based around civilizations and such. Or maybe I should say that when I do, I usually use an existing ones as a sort of template.

>First and foremost, how do you build a fictional economy and do you even need to?

As with all things, it's only important if it's a part of the story.

Making them is pretty simple though. If you have a medieval town located in the woods, something was there that caused a settlement to form. Maybe the wood is of good quality, or the nearby river has lots of beavers to skin for hats. So you have a lumber yard/skinning hut that exports its goods to bring wealth into the town. If there are enough people doing it, other people move in to provide services to the workers, such as the town doctor. Boom, basic economy.

>Second, do you need to create conlangs or can you just reference the fact that a character is speaking X language and leave it at that?

If language barriers are not a part of your world, you don't need to address them. Otherwise, I usually say that someone is speaking in a foreign tongue. Sometimes I'll use brackets to make it apparent someone's not speaking the protag's language if I want the reader to know what's being said. But that is a stylistic choice and not the only solution.

>Third, is it possible to worldbuild a faction or civilization that has no culture? If so, what would that look like?

What's your definition of no culture? The closest examples I can think of would be a melting pot where there are so many cultures they all sort of blend together, or a society without traditions and standards of any kind. Maybe very early cavemen didn't have culture? I would think that any group of people are going to form their own beliefs about how things should be done and a culture is going to come out of that.

>Fourth, if your factions are run by gods then do you even need to go into depth on anything but the deity in question? And by deity I mean the omnipotent, can do anything that it pleases, kind. Not the Greek or Roman kind.

Yes, because followers of said deity seldom share the exact same mindset. Maybe if said god is a wicked creature that uses their subjects as an extension of their will, but even the Ossiarch Bonereapers in age of sigmar, skeletons that are an extention of Nagash's will, have their own history and culture apart from the necromancer that's brainwashed them all.

>Fifth, do you start fleshing out the world itself first, timeline of events, or both?

I usually world build to add depth to a story I want to tell. So I usually figure out details about the world before working on the timeline that created that world. I think it depends on what interests you more.

First and foremost, how do you build a fictional economy and do you even need to?

I don't think I can answer this question simply and I don't have time to attempt to go in depth so I'll have to give it my best.

Super simple answer:
No

But it depends on what you're doing. If it's a setting of just some dudes being dudes and the rest of society exists in the background then an economy is not that important. You *could* do an economy and declare at some point in the course of the RP all the prices at the shop are suddenly going up to represent some abstract world event. Or even if the RP becomes set in a town the entire town goes on lockdown for any reason and prices sky rocket like they do in Pathologic

Second, do you need to create conlangs or can you just reference the fact that a character is speaking X language and leave it at that?

Not unless you're super autistic. You can otherwise get by by not mentioning it, or just ripping an entire RL language but renaming it the way say: Disco Elysium does.

Third, is it possible to worldbuild a faction or civilization that has no culture? If so, what would that look like?

No. There is no such thing as a total absence of culture. Culture represents the totality of the relationship of a society to the material world, including the objective and subjective explanations a group of people have to explain the world (science and religion), and a whole host of historical relationships with themselves as a group and others and influences. A culture is the intermarriage of present material circumstances and the force of all history behind a group. If you were to create a group out of nothing and drop them into a world in which they have no context they *will* develop a culture unless they are some kind of animal, but even then it's known that some animals such as whales do develop something which can be called culture.

Fourth, if your factions are run by gods then do you even need to go into depth on anything but the deity in question? And by deity I mean the omnipotent, can do anything that it pleases, kind. Not the Greek or Roman kind.

Depends on how much of a character they aree.

Fifth, do you start fleshing out the world itself first, timeline of events, or both?

I start with the immediate physical environments and as I map them out I might create a summarized geologic history to explain features I am currently drawing onto a map and go from there while thinking about how and how much it matters someone else can *read* the intent of the map the way I did, or how I can enforce the intent of the map. Other considerations depend on various bits and pieces of set dressing (lore) and how much I want there to be. The rest is weaved in by others as they join and contribute.

Sixth, how do you come up with names for things if you don't have a conlang? What generally goes into the creation of such names or their meanings?

See my answer to the conlang question. If no conlang: just rip of IRL languages and the general idea of how places are named or just vibe it out.

Do you build dynamic worlds that are constantly evolving or stick with static ones that never change?

I've never dealt with anything of that scale of time.