Formula for projects due to start in X no. of days

Hi again,

Please need your help to correct my formula below. I wanted to count the number of projects that are due to start 14 days based on planned start dates but I am getting "Incorrect Argument Set" error.

Please don't get confused with the formula. The projects I created have 5 subtasks and as an alternative solution, I chose to pick up the numbers from the category column (the classification of the project) that are not blank. I'm not sure how to count by the projects headers hence my formula looked like the below.

=COUNTIFS(Category:Category, NOT(ISBLANK(@cell)), [Planned Start Date]1:[Planned Start Date]233, >TODAY(14))

Kind regards,

Grace