Things you CANNOT do

Eat your heart out.

Wear your ❤️ on your sleeve

Laugh your head off.

Have feet of clay
Or a tin ear
Or a mouth like the bottom of a birdcage
Or turn the air blue although I've given it a good go

You can't be as drunk as a skunk, or as pi**ed as a fart.

...or seven sheets to the wind.

Have cloth ears.
Die of embarrassment.
Turn green with envy.
Keep it under your hat, well not if it is a secret,

Drive someone up the wall.

Sleep on the head of a pin

Your heart-strings cannot be tugged.

Jump from the frying pan into the fire (unless it was a huge frying pan!)

Would die for

Am I being a pedant by saying that these are all figures of speech, not things you can actually (lietrally?!) do?

My mum says I can hear the grass grow.

Scramble your brains, OP!

Turn green with envy

Well it is Pedant's Corner Magrithea!

I don't think it really matters that the title is not quite specific enough. Phoenix has clarified exactly what she meant, by offering examples to start us off. We understand what she means, otherwise there wouldn't be so many responses.
It's intended to be a lighthearted thread, which I've thoroughly enjoyed reading. Thanks Phoenix!

Climb every mountain (although Munro collectors try hard)

Meet yourself coming back.

laugh your socks off

lose your appetite and find a horse’s

(........) until the cows come home

my current "beefs" though perhaps not completely this thread

twice .. seems to have disappeared from the English language, everything (well nearly everything) is two times..

and you and me.... now everyone, ! says me and you... I was taught to always put the other person first,,, perhaps language follows how people behave?

You cannot:

Be born with a silver spoon in your mouth

You cannot:

Cry your eyes out

Be joined at the hip.

Have a baptism of fire.