If you want to invest in Indian equities, though you are based Germany, the answer is that you can, as an NRI invest in equity mutual funds.
Assuming you have a PAN card the investment process is quite straightforward and you get access to major mutual funds.
Coming to the question of which shares/funds to invest in, this depends on your investment objective, horizon and risk appetite. You can get a risk profile done here.
Since you seem to be at the early stage of your career, this can be a mix of long term equity (you have time on your side) and some liquid funds to ensure liquidity for immediate needs.