2060 is enough at rhino 6.0?

I will buy rtx 2060 or 2070 for rhino
but 2060 is cheaper than 2070
2060 is enough at rhino6.0?

It always depend on what models you are working on and if you want to use the GPU for rendering.
Generally a RTX2060 is very capable and more than enough for all the usual stuff you do with Rhino6. It is also very good for rendering with cycles.

You’ll be fine with the RTX2060.

Put the money that you save with the 2060 over the 2070 into a decent mainboard and ram.