Some new doubts

Hello, everyone!

Please, correct the following sentences and answer the questions. I'm learning the Present Perfect and prepositions.

Put the chairs around the table.

Look how he's sliding down!
Or
Look how he slides down!
For example, he is sliding down on his tummy.

Let's set the table for dinner! Ah, you have already set the table...

The table is set with spoons and plates.

Put the frying pan on the stove. Ah, you have already put the frying pan on the stove...

"Put the kettle on" means to start to boil water in a kettle. What about "put the frying pan on the stove"? Somebody can place the frying pan on the stove, but forget to turn the stove on. Right? In this case, I can ask:
Have you turned on the stove?
And in   AT the end of cooking I can ask:
Have you turned off the stove?

Let's stop here and get/buy two ice-creams: for you and your sister. // to get = to buy?

Let's go for ice cream. // I like this sentence. Does it mean "let's go to the store to buy some ice-cream"?

Thank you very much for your help!

** you are perfect