Without knowing how your database is set it’s difficult to say…

But I’m assuming that ‘Bike’ is a datatype, and so is ‘Colour’.

From the image above, you haven’t set a content type for you page ‘add colours’ so you can’t pass any data directly to that page (unless you use url parameters).

So make sure you set the content type for that page to ‘bike’ so that the page expects to de sent ‘bike’ data - then you can pass the ‘bike’ created in step 1 through to the ‘add colours’ page with the ‘go to page’ workflow action.

It’s not clear what you mean by ‘add a bunch of extra items’? What kind of items? And where/how are you intending to add them? And add them to what? (the ‘bike’ presumably?).

Your repeating groups on both pages are currently set up to display a list of ‘Users’.

I’m not sure what you’re trying to display in the repeating groups?

Users? Bikes? Or colours?

Whatever it is, you need to set that as the type of content for the repeating group, then define which ‘things’ of that datatype to display using the datasource input.