I saw many people confused asking what this site is, I have been using it for like 1 year i think.

VGen is mainly a commissions site, offering protection to clients to not run the risk of getting scammed.
And protects the personal information of both client and artist (If paypal is not used, there the protection depends on paypal)

To be able to sell art in the site, you have the next options:
-Get the invite code from their staff in other sites like Twitter (they will check your galleries and stuff)
-Get an invite code from a verified artist that really trust you. Marking that, because if their invited user breaks a rule, it puts the inviter artist's account at risk. (So don't ask me for a invite pls)
That helps to filter people and suspicious accounts to protect clients.
Clients won't need an invite code to use the site.
And can even purchase as a guest.

About the protection to artists, it depends on the payment method you use to get the muns. If you use Paypal, your protection will depend on Paypal, not VGen.
And then there is their option to save the money there via Stripe, and you will be able to withdraw directly you your bank after you save more than $50, there VGen should protect you against suspicious activity.

Vgen will always charge a fee no matter the paynent option you used.

As an artist you can offer services, and upload your art as a gallery.

https://vgen.co/sifyro

This is my page for example. Currently my commissions are closed. People can follow the service they are interested and will get notified when I open.

When I open commissions, the potential client will be required to fill the form (usually helps to calculate the price, also it will ask your references) , and agree to the ToS of the artist (example, some artists limits the number of revisions, I prefer "surprise me" commissions, which means no revisions). If everything is good for everyone, the client can proceed to pay.

I will get notified about the payment, and the filled form will appear in my "to-do list" , similar to Trello.
The artist can send WIPs to get approved or directly the finished art , depending on what you agreed.

The client and the artist can rate each other from 1 to 5 stars.

Verified artists can also sell art packs, customisable 2D models, etc. I mainly use that feature to sell emote packs :3

https://vgen.co/sifyro/shop

I have been told that buyers gets notified each time I add new emotes to packs they purchased before, and can download the updates without extra cost.

When you finish a commission there, you can chose the option to add it to the portfolio (gallery). The submission will be marked with a green badge if it was a succesful commission done in the site:
Example:
https://vgen.co/sifyro/portfolio

That helps clients to feel safer when commissioning an artist and not a random scammer. They can also check the artist stats in their profile, that shows how many commissions they have completed in site, and see the public reviews clients leave.

And that's all the info I can give from my experience :3
I honestly prefer notifying my clients in my discord server that's dedicated to commissions. When I plan to take a LOT of "surprise me" commissions at once (usually emotes/headshots), I ask them to fill the VGen forms.

This is my commissions discord server: https://discord.gg/4cB3M8BY6