FIND Returns the starting position of one text string within another text string. FIND is case-sensitive.
Syntax
FIND(find_text, within_text[, [start_num][, NotFoundValue]])
Parameters
find_text – The text you want to find. Use double quotes (empty text) to match the first character in within_text.
within_text – The text containing the text you want to find.
start_num – (optional) The character at which to start the search; if omitted, start_num = 1. The first character in within_text is character number 1.
NotFoundValue – (optional) The value that should be returned when the operation does not find a matching substring, typically 0, -1, or BLANK().
Return Value
Number that shows the starting point of the text string you want to find.
Reference Data
https://docs.microsoft.com/en-us/dax/dax-function-reference