Correct, it is a text my.token.
No, it’s not! You’re describing an existing Velocity {{my.token}} that’s reading a field from Custom Object record.
Now first: using .get(0) on a list is never recommended. You should consider the list to be unordered, so getting the 0th item (i.e. the first item) is getting a random item. Explicitly sorting and filtering, then locating the correct focused record, is the correct practice.
Assuming you get past that and have a date-like String field, you need to convert it to an actual Date using the methods illustrated here.
The output format string for “January 5, 2023” is indeed MMMM d, yyyy.
But input format you’re using isn’t really yyyy-M-d H:m:s as you typed. It’s yyyy-MM-dd HH:mm:ss, which is called $ISO8601DateTimeWithSpace in the post. (Though technically it’s not valid ISO 8601 because of the space, and I should’ve called it $NonISODateTimeWithSpace.)