Best way to create form with multiple cascading drop downs.

I want to create or find template to show cascading drop downs. Example-first dropdown HVAC, Electrical, Mechanical. Choose HVAC. Second dropdown show all items associated with HVAC such as Heating,Ventilation, AirConditioning. Choose Heating. Third drop down shows all associated to Heating such as Boiler, Heat Exchanger, Hot Water Loop. Choose Hot Water Loop. Forth drop down shows all associated with Hot Water Loop such as Pump Set, Control Valves. Choose Pump Set. Fifth drop down shows all associated with Pump Set such as Pump, Motor, Strainer, VFD.

Any info is greatly appreciated.

You could use data validation with a drop down that reads a list. Make the range of cells for the first dropdown, then make the contents range for the second dropdown change according to the item selected in the first dropdown and so on.