Limiting Characters in a Cell/Date Validation

I want to limit the number of characters that a requester can enter into a cell via a form. The use case is that the user is entering a new request for consideration into an Intake Form. In assigning a name to their project request, we want to limit them to no more than 25 characters, based on limitations from another system. Is there a way i can limit these characters?

In the same form, I want to prevent people from entering a Target Finish Date that is before the Target Start Date? Does anyone have ideas on how to do this validation? I am currently doing a conditional formatting of dates that do not comply, but it allows the user to enter them that way.

I appreciate any suggestions on both of these questions.

Thanks,

Steve