Honestly if you want to learn basic flat-pattern drafting, there are a ton of great books out there with all the information you'll want. I used this one when I was getting started and liked it, but there are others. If you're anywhere close to a city, most larger libraries are going to have at least one pattern-making book in their collection. If you live close to a university with a costuming or fashion major, that library will likely have a wider array of resources. Bonus: free or very low cost compared to one of these online courses.