You need to re-read theory on what an op-amp does if you think this circuit is correct.

In every book/online this the exact circuit. For my circuit R=20Kohm

1. It's not the exact circuit. + / - are swapped, that's kind of important 2. That circuit assumes a perfect op-amp with no voltage limitation and infinite power rails. You need to understand HOW the circuit works so you can adapt it to what your requirements are and the limitations of your building blocks.

Yes, I am kind of feeling that I'm missing something, but not able to figure out.