How to pass string split to a stored procedure?

Basically, don't use comma delimited data anywhere near SQL - it's always going to be a PITA at some point even though it is possible. For example: Using comma separated value parameter strings in SQL IN clauses[^] and Converting comma separated data in a column to rows for selection[^]
If nothing else, you may introduce an SQL Injection vulnerability which could compromise of destroy your DB.

And that syntax you show makes no sense at all - which is why SQL is rejecting it.
I assume you are trying to execute the SP once for each string in your CSV data - if so, you will need a loop with the SP EXEC inside it - but I'd strongly suggest you find a different way to achieve whatever it is that makes you think this is a good idea!