Just because your friend is a continental-style knitter it doesn't mean that it will be your preferred style or that you will hold your needles the same way.
Everyone's hands are different - individual like fingerprints - shaped by all the things you do in your life.
For example, I enjoy fencing (the sword type) and how I hold my sabre has had an influence on where the strength in my hands lies and that effects how I hold my needles and what is comfortable for me. I have also knitted every day for a very many years, which means I have had plenty of time to find a knitting style that suits me.
Don't worry if you hold your needles from above or below - choose the way that feels right to you. Think about whether you are comfortable making stitches and whether you like how your knitting comes out - consistent stitch size, good tension, etc. If you aren't happy it is time to adjust your style, otherwise keep going.