Database aren't anything to do with .NET - particularly Server based databases, which run as a separate process, often on a separate machine to the application and / or VS.
While it is possible to create tables in VS, it's a clumsy tool and most DBs are created in SSMS or teh MySql equivalent (
MySql equivalent for ssms - Google Search[
^] may help here)
If your tables are "different between MySql and MsSql" then you need to look very closely at why, and at how you created them - some of the datatypes are slightly different, but they cover the same range of data storage.
That doesn't mean that your application will work the same without changes other than the connection string - it won't. You need to swap it from SqlConnection, SqlCommand, and such like classes to their MySql equivalents, as well as changing your connection strings, checking your SP's, Triggers, and so forth.
One thing you could do is try exporting your Sql Server DB as a set of CREATE commands, and then modifying those to match what MySql expects.
And we can't do any of that for you: we don't have any access to your data, much less your code!