Hello, many websites offer courses online, however they tend to use the most complicated tools and the cost it's outrageous. Check out this one, FREE for a very limited time: http://bit.ly/free3dhome

Udemy is one of the best collections of online courses since they are taught by experts in their own field. These are video courses, some of which are free, for example, if you search for Udemy in the Google play store, you will find over 200 free courses that vary by topic, each one is a course containing several detailed videos. Udemy courses on interior design are at https://www.udemy.com/courses/Design/Int...

You can also use the google operator "filetype:pdf" before your search term to find available pdf documents about that search term for example:

filetype:pdf interior design

at a 4 year college