Relationship between two Combobox in Access

Question

I’m trying to relate 2 Comboboxes in Acess, but I can’t find how to do it.

This is my form, I would like when selecting the value in the field "Expense Type", the values of the field below, "Expense", to be related to the field "Expense Type":

For example, when selecting "FIXED" in the "Expense type", the values available in the "Expense" field are only "FIXED" and if I select "VARIABLE", the list of the "Expense" field would change to the related values.

Currently this list is appearing in both cases, "FIXED" or "VARIABLE", but I would like to do it in some conditional way, so that depending on the value selected in "Expense type" your respective list appears in the field below.