Hello @maxb and welcome to the community!
Suggested dB structure
Competition
Title (text)
Entries (list of entries)
Entry
Title (text)
Dashboard
Create a page named dashboard
Set it to be of type “competition “
Among various elements like a header etc etc … add a repeating group to list your entries
Set the rg type to be “entry” and set it’s data source to be a search of current page’s competition’ entries
When you navigate from the origin page where you chose a competition entry … make sure to send that competition object via the “go to page” action where there is a box to send data and choose the competition entry that you want to see on your competition page.
The above is just an illustrated example of how this could be done. Of course, you can do it in many different ways.
This should get you started and hope it helps a bit 