Yii2 How to handle dynamic fields in a model?

Question

Yii

There are obynchchy fields that belong to the same model. And there are also fields that are added dynamically, they need to be written to another model.
How to write them correctly, what to specify in the rules?
What if there are 2 fields, for example 2 text inputs?

Answer 1

In one model, some fields are validated, in another, others. And it is worth writing them not in the model, but in the database using the model.