pass data from one model to another

Hello forum, I have a model A with :

dataA1_pk

dataA2

dataA3

and a model B with :

dataB1_pk

dataB2

dataA1_fk

PKs are AUTO_INCREMENT,what I want is that: when I insert data model B in my view create, in the field dataA1_fk insert automatically the field to modelA, I want to work as a dropdown , but in a textinput , such as PK are integers I need is to show another field that gives me information validates. nay idea??