>Would programming be good?Pays well, there are several fields. I will highlight the web developer route which is the easiest yet pays very well. You can design the product, you can create an image how the interface would look like and work like (UX, UI designer), you could work on the backend or you could make the frontend or you could deploy and maintain the servers (devops). You could even go full-stack (everything that I mentioned).
>If so, what would that entail?Pretty much everything in connection with the company and product in hand. Even helping customer support and testing the product and collecting feedback.
>Would an online course give me the qualifications I would need?No qualifications are needed. You simply have to be able to do the job. Start on udemy, then pivot to YouTube for faster learning once you understand the concepts. Avoid the "tutorial hell".
Listen the Futur podcast (
https://open.spotify.com/show/5K96ryZCjCmxqMzEotvS8h) so that you will gain the understanding how to get clients and jobs (you need it trust me, even if you are not freelancing).
>How long would it take to learn?9 months tops if you are consistent. Make sure not to do it alone, get some help from someone who is already doing it and can help you if you get stuck.