Per the instructions in the rapid developer course I wrote the microflow out word for word and keep getting this input error. I have tried changing it around a number of different ways which have all led to more errors. Its probably a silly question but I am starting a new job remotely and have no other way to fix issues.
You have several things wrong.
Firstly, the function is called addDays (notice the uppercase D for Days). Mendix is case sensitive here.
Secondly, the first field is a DateTime value. so for the current date and time use [%CurrentDateTime%]
Lastly, the second field has to be an integer. So to add 5 days, just drop in 5 there.