TextBox Validation From Database

Question

 

IN Form1 user enter the car names e.g(HONDA, TOYOTA, BMW....) which same in the Table1. In the Form2 user enter the colour e.g(BLACK, WHITE, SILVER which  save in the Table2. In the Form3, i want when user try to write wrong spelling " HONDX  "in the textbox, new help form which have data from Table1 user select from there then go to the other textbox.
But if user write the correct spelling " HONDA " in the text box no help form shows just go to the other text box.

Please tell me how i validate TextBox data from the DataBase table.