There are multiple low-cost and free course options on the internet. Please see some below:
Youtube.com
Youtube is not just a video platform. The platform has multiple courses and information if you are looking in the right places.
Udemy.com
Udemy is a course website where you pay a small fee to buy a course. I have found multiple courses in topics I was interested in.
Coursera.org
Coursera was started by a former professor. The site has classes from multiple different schools and a lot of them are free. I really like the learning how to learn course here.
Khanacademy.org
Free website with a lot of educational courses taught in school. If there is a particular topic that interests you can check out this website.
Skillshare.com
A website where people share skills and for a small monthly subscription you can take their courses.