Hi!
By default, vendors configure their shipping methods in the “Settings” menu (see the screenshot below). We made it that way because shipping methods aren’t something that vendors configure or change every day.
For now, changing that behavior requires code modification. But in CS-Cart Multi-Vendor 4.16.1 the vendor dashboard will be much more configurable, including menu customization. So you’ll be able to show “Shipping methods” where you want them.
P.S. Here’s a sneak peek of something else that is coming in version 4.16.1 — onboarding guide for new vendors. You’ll be able to customize it with your own steps, videos, etc.