I may be wrong, but I don't think a control like CheckboxBar has been implemented. The closest option is "Boolean", but you would have to use it for each option. You could make the suggestion below look better with some more sophisticated FormObject options (put all the checkboxes in a single row)
kform = FormFunction[{"First Name" -> "String",
"Last Name" -> "String", "Email" -> "EmailAddress",
"ProductA" -> "Boolean", "ProductB" -> "Boolean",
"ProductC" -> "Boolean", "My Product " -> {A, B, Cc},
"Type" -> {"2 ", "1 "}}, fu][]
