..I am looking for a free course so that I can understand the photography a bit then I will invest money for more deep knowledge. overall thanks for your suggestion if you have any free course that would be great.
Why not just dive right in and take some pictures? You will have questions, everybody does, so then you post an image on here and ask your question. We have seen photographers start out at the very beginning and eventually become good enough to start charging money.
I agree with Designer, there's no cookie cutter way to learning "photography" as a whole, and definitely not a free way. I am here for the same reason as you are, Andy, and utilizing the constructive criticism from others on this site can be a good way to learn from your own mistakes/experiences.
Take some photos, see what works and didn't, what YOU liked and what you didn't, and then just try again accordingly.
If you are really trying to learn, what worked for me is seeing pictures that inspired me from other (much better) photographer's, and then trying to capture a similar effect through my own pictures. It helped me realize all of the different factors that can go into one single photo, and I am still learning.
It will come down to how much you are willing to learn, paid or for free.