如何动态填充下拉列表中的值

Question

I have the below source data(the original data has thousands of rows)

Form  field 
Form1 field11
Form1 field12
Form2 field21
Form2 field22

In a separate sheet, I want to have 2 dropdown lists in field A1 and B1.

The drop-down list in A1 should populate the list of forms eg Form1, Form2 ,etc.

The drop-down list on B1 should populate the field based on selection from A1.

For ex if Form 1 is selected in A1 ,B1 should populate field 11 and field 12 in drop-down list.

Answer 1

screenshots (in reverse order) and function (1st step, bottom)/ sheet here refer:

4] Result

3] Validation list 'selected cells' relies upon named range:

(make sure to include # at end to extend to bottom of spill range - assumes you have Excel as part of Office 365 package)

2] Additional spill range specified in cell F4 as follows:

1] Filter function:

=FILTER(E4:E7,D4:D7=H3)