TO be honest, you'd probably be better off doing that in a presentation language where you have access to the users context information - including his language and date format preferences - SQL string handling isn't good, and while processing English month names is relatively trivial (as Richard has said, a lookup table will do it) it becomes a lot more complicated if you need to handle any international month names.
Plus, it gets a bit nasty with two digit years, as the data you have to prefix them with could be in two different centuries - and you have to decide which based on some rule you have to invent!
If you do decide to do it in SQL, then I'd strongly suggest writing a user function to do the conversion as it will make your life a load easier ...
User-Defined Functions - SQL Server | Microsoft Docs[
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