There are no tools for this, so you have to do the conversion manually.
This is a pretty straight forward conversion, but normally I would start with documenting the functionality of the SP. It is good for the understanding to have your procedures documented.
Then check out the MySQL site and read the documentation for their stored procedures.
The DDL syntax is similar and the SQL syntax is the same.
Chapter 19 Stored Programs and Views[
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13.1.12 CREATE PROCEDURE and CREATE FUNCTION Syntax[
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MySQL Stored Procedure[
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