Custom Profile Option accessible via REST API

Summary:

Content (required):

We are designing a VBCS application for CX Sales. In the VBCS we will have a logic that will be enabled based on a given date. We want the date to be updatable in CX Sales by an administrator. For this scenario, I am thinking of using a custom profile options but how do I perform the following:

1. How do I create a custom profile option whose value is accessible via REST API
2. How do I access the custom profile option and value via REST API?

Version (include the version you are using, if applicable):

22D

Code Snippet (add any code snippets that support your topic, if applicable):