You didn't mentioned your UG degree if any. But in general apart from such courses to be a teacher you need a PG degree at least. Now as you want to work as a teacher in Vedic Mathematics then you can join institutes which teaches the students Vedic Mathematics at a very initial stage. As you haven't mentioned the name of your state or place it hard to say but in kolkata we have 'The Vedic Maths Forum India '. You can get their details from the google search.

Also you can teach vedic mathematics in Youtube or other platforms. It can be tedious at a first but if your content is good then you will reach to a good level.

I hope my answer gives you some insights. All the very best for your future endeavors!