Populate a List Column from lowest level selection in nested choice

Question

I'm using the default 'Issue tracker' template list in SharePoint online/365 and want to add a column that will store name of the Product or Group an issue is related to from a nested hierarchy of 'Group' or 'SubGroup' or 'Product'.

Unfortunately this is proving to be very difficult with my very limited knowledge of SharePoint and feature names.

Assuming I have the following 'Product' category structure;

| Group | SubGroup | Product |

|-Cutlery
|  |-Spoons
|  |  |-Dinner
|  |  |-Dessert
|  |
|  |-Forks
|     |-4prong
|
|-Bedding
|  |-Sheets
|     |-King
|     |-Queen
|
|-Paper
|  |-
|     |-80gsm
|     |-120gsm
|
|-
|  |-
|     |-Chair
|     |-Door
|    
|-Flooring
|  |-Cement
|  |  |-Polished
|  |
|  |-Floating
|     |-Bamboo
|     |-Pine

How should I store this reference data? All in one 'Products' list or do I need to split it into 'Group', 'SubGroup' & 'Product' lists?

How could I show filtered dropdowns for each of these 3 categories in the 'New Item' form for 'Issue Tracker' list, where only the lowest selected level value will be entered into the 'Product' column in Issue Tracker list.

Desired use case outcomes

1. User selects 'Bedding' from 'Group' dropdown. 'SubGroup' dropdown will only display 'Sheets' and 'Product' dropdown will only display 'King' & 'Queen'.
2. User selects 'Bedding' > 'Sheets' > 'King'. Only 'King' will be entered in 'Product' column of 'Issue Tracker' list.
3. User only selects 'Bedding' > 'Sheets' but no selection from 'Product' dropdown. 'Sheets' will be entered in 'Product' column of 'Issue Tracker'.
4. User only selects 'Bedding' but no selection from 'SubGroup' or 'Product' dropdowns. 'Bedding' will be entered in 'Product' column of 'Issue Tracker'.
5. Without making a selection in 'Group' nor 'SubGroup' dropdown, user can directly search and select from 'Product' dropdown. Selected 'Product' value will be stored in 'Product' column of 'Issue Tracker' list.

Answer 1

I am afraid that SharePoint does not have an out-of-the-box cascading drop-down list. You can refer this article to create Terms as an alternative：3 alternatives to building cascading drop-downs in SharePoint