To design product with Bits, you may use the Figma design system library. The Figma library is an interactive playground that maps to the Bits source of truth. To access Figma, please reach out to UI Engineering or Design who will make you an account.
The Figma component library should contain all the components that can be found in the Bits source of truth. To enforce consistency across the site, you shouldn't need to make anything from scratch. If you want something new, talk to design and the ui-engineering teams. If both teams agree that it is a worthy addition, either your team or ui-engineering will work with design to implement it and get it included in the @freelancer/ui module.