Well to sell courses on cooking, there are 2 methods you can try. In general, one is through pay ads, and the second one is organic traffic.
So you can either
1) Invest in some ads or buy shouts on Instagram (maybe even some other sites) from influencers in cooking and food. I am not sure how much ROI you can get, you will need a hell of a good offer, as cooking related stuff is not something most people are looking to buy. If you think you will make money on this if you don't know about optimization and marketing forget about it. You will probably lose money unless you know what you are doing.
2) Organic traffic is better for beginners but it is a longer process. The best way about this would be to create your site and insert courses. Make some youtube video, try to rank it, post it on food forums, guest posts, etc, etc, This one is usually free (or very cheap to start with) but there is a learning curve. A big one, at least if you are the first time dealing with this. I don't know your skills so I don't know how successful you can be at this.