Creating Dependent or Cascading Drop Downs

I am currently editing a workbook that will be used by multiple people. I want to limit user error so I need to create some rules within the drop downs that limit the number of choices depending on how they select the first two columns. For Instance, my first column has 5 choices. My second column will have anywhere from 1 to 4 choices, depending on first columns choice. My third column will be dependent on the first two choices. It could have 8 choices available in column 3 or just one choice. Further, if columns 1,2,3 have a particular set of values in them, then columns 4-6 are limited to one choice as well. Is there any way to do this? I feel like some of the formulas I know for Indirect and Substitute may work but I feel I will have to spend a lot of time to build out many name lists for this to work properly.

Have a look here https://www.contextures.com/xlDataVal02.html

Thank you. I have been reviewing that site as well as creating Excel Data Validation tables but I feel they are falling short of what I need. I don't have the knowledge to create a dynamic formula that will fill the role I need. I have already created a drop down in Column A that is program and a named range for that is listed in the source field. Column B is program type and has dependent drop downs for what is entered in Column A. Column C is carrier, Column D is carrier plan, Column E is contract type, Column F is Reimbursement Type, and Column G is Par Flag. I have multiple choices in these columns that is a basic drop down list which is open to user error. However, I want to keep these open drop down choices, except in instances where there are required choices based on previous columns Here are the rules I am trying to solve for:

1. Program: Commercial and Program: Exchange should never have N/A in any column with the exception of Program:Commercial - Program Type:Other.
2. Program: Medicare - Program Type: Traditional should always have Carrier as government and remaining columns should be N/A
3. Program: Medicaid - Program Type: Traditional should always have Carrier as Government, free text Medicaid followed by state symbol in Carrier Type column and remaining columns should always be N/A
4. Self Pay should always be Program: Other - Program Type: Self Pay and remaining columns should be N/A
5. If Program: Other - Program Type: Other is selected, remaining columns should always be N/A
6. Any government carrier should always be N/A for Par Flag.

Is there a way to create a dynamic formula for drop downs that would allow for selections and limit drop downs in these specific scenarios. Everything I think of would fulfill one rule, while failing in other rules. I can't think of an extensive IF function or other way to set this up that would encompass all of this.



Thank you for any insight that can be given.