Understanding de and ni particles

a: nodo ga kawakimashita ne.
b: ee nani ka nomitai desu ne.
a: asoko de nanika nomimasen ka
b: ee soo, shimashyoo

this is the conversation among two people and i would like to understand as to why de particle is used here (tell briefleyl) and if possible pls do explain me more about de and ni particle because i am very confused when to use what with places. pls reply asap

So you are asking about the difference between �g(place) ni�h and �g(place) de�h with verbs?
Very briefly:
- [Place] de = �gin�h a place. You do something �gin�h or �gat�h a place.
- [Place] ni = �gto�h/�hinto�h a place. There is a sense of movement.

For example:
- Mainichi gakkoo de benkyoo shimasu. (Every day I study �gin/at�h school.)
- Basu de gakkoo ni ikimasu. (I go �gto�h school by bus.)

So in that conversation,
- Asoko �gde�h nanika nomimasen ka�h
Is saying �gwhy don�ft we/shall we drink something THERE?�h meaning �gdrink AT that place.�h (Imagine you will be sitting or standing �gin�h a place as you drink.)
Person b could have answered this way (instead of the last line.)
- Ee, soo shimashyoo. Asoko "ni" ikimasyoo. (Yes, let�fs do that. Let�fs go there.) (Imagine the action of GOING/WALKING there, so there is a sense of direction/movement.)