That’s a very open ended question…there is so much to learn, practice and master.
- To start I will suggest you to buy any entry level DSLR with the bundled lens and use it as much as you can. Don"t spend too much.
- Read your camera manual and read again/google till you understand.
- Try different setting till you know how it effects your picture.
- Once you develop a good understanding of you gears that will be the time to start learning the difficult part(lighting, composition etc.)