Hello! Any advice on the brushes and techniques would be really appreciated! Thank you
Forget software. It helps AFTER you get plausible results with traditional drawing tools on paper. Get a pencil.
Software doesn't invent the needed forms, you must be able to imagine them and present them with lines, curves and shadings. If you are a beginner you must walk the same route as the others who can draw. Get books, study and draw and draw and draw...thousands of drawings to develop the skills gradually.
Competent teachers can help substantially.