First of all you should think of what should be presented on dashboard, you have chosen some entities already. From that entities there might be different criteria for showing items:
- One will show latest products
- Other will show last edited posts by user
- And maybe
saleswill show highest sales?
There are ready components which allow creating date input user friendly, or at least it looks like user friendly.
Date picker input is pretty popular complex input type, where user have to choose predefined data in predefined range and format. It is used widely, everyone know how to use it and users don't have to wonder what date format should be used.