How do you go about building an admin dashboard for a Laravel webapp?

If this is for a client or project, I'd likely use something off the shelf unless that doesn't fit the bill then it would be dependent on the project requirements.

Personally I'd focus on building the core product itself, not the admin dashboard and just use a off the shelf option. Why reinvent the wheel if you don't have to.

To answer your staff credentials question, that's entirely up to you. I would have all users in the same table and just assign roles which have permissions to them.

I wonder, how would you go about building a dashboard for laracast, where you can add videos, sections for the videos, new categories etc via the back-end?

@aurelianspodarec This would just be a case of creating controllers and views for those resources. So an Admin\VideoController, Admin\CategoryController, etc.

Would the staff credentials live in the same database as 'users'?

I usually keep users in the same table, yes. A user is a user. Even if there are “regular” users, “admin” users, or whatever other type of user. You can add roles to users, and then use authorisation to determine what a user can and cannot do based on the role(s) they have.

In my case, would you perhaps just use Vue/React for the admin dashboard, and let it be a separate entity from the webapp?

So Blade + Vanilla JS for the webapp, and Vue/React + API for the admin dashboard, so I can upload images, create records, update records etc...

Up to you. There’s no one way to go about things. You can either build something from scratch, or use something pre-made like Filament or Nova and customise it to your needs.