How do I put in the campStartDate on Build an Autolaunched Flow module?

Hello all,

I am trying to put in the camp start date via a formula but I am not good at coding and at this point am not sure at this point that it is supposed to put in via formula. All I know is that it will not accept text as an option for the date field.  Can someone please help with some suggestions?

Thank you,

Wendy La Pume