If you want to create validations on a page, validating the type of input and the data itself, this is how to do that.  
 

Step-by-step guide

Create an attribute

Follow the guide how to create Attribute.
Make sure the attribute is put on a page and is not read-only. 

Create a validation rule

Follow the guide how to create Validation rule.

Validation rules check whether the data is valid, so if the expression in the validation rule evaluates to false, the rule will trigger a validation.

Add validation rules to the attribute.

In the attribute screen, add a validation rule and select the created rule.


Validation types 

Validation types are added to an attribute in a similar way to validation rules, select validation type as validation to be added and click add.

Follow the guide how to create Validation types to implement validation types.