How to prove that nothing is not something?

Semantically.

Think, `Stephen Hawking`, and there you have it, if you see what I mean.

Well, let's see. If you can define for us what "nothing" is - you CAN'T - then maybe we can address the question. Is what is inside an empathy glass "nothing"? Is what is deep space "nothing"? Perhaps we can define it as that which a dead brain thinks about - what do you think? Or should we define it as the absence of what we would like to "see"?

“Wisdom says I am nothing. Love says I am everything. Between the two my life flows.”

– Nisargadatta Maharaj

Did you get the point?

meditate

You cannot prove a negative.

You can't because nothing IS something, which is easily proven. Even if you can imagine a universe or state of existence that contains nothing, that universe or state of existence is still "something".

Define clearly that "no" means "no" and "thing" means "thing." No x is y = no no-thing is some some-thing. If you choose a von Neumannian second-degree framing of "no thing" = reified null set, simply be cognizant of your or someone's second-degree framing step, lest it become an equivocation.

Nothing as a concept IS something, so you may find it difficult as it doesn't exist physically in reality

What do u mean like nothing is nothing nothing isn’t a dog or a bed or a chair get them to tell u if nothing is something then tell me what that something is then they wouldn’t know what to say like say to them this “ if nothing is somet then go on tell me what it is”