It’s quite interesting but I’m pretty sure we don’t have such a “generic” expression or phrase to say so.

For you example with salad, we may say (with sarcasm) something like:

Eh t’étouffes pas hein !

For the fisrt one, you may hear:

Regarde où tu mets les pieds quand tu marches !

So as you can see, there is no ordinary expression like the use of “much” as you explained. You might use common expressions we usualy use depending on the context.

I don’t think there are a perfect translation.

You can use “Apprends à X”. But it can be a little mean, so use it carefully.

You can use it with good friend when they fail to do something simple.

Exemples :

“Apprends à macher”

“Apprends à manger”

“Apprends à marcher”

The expression that most closely resembles in meaning and form, in my opinion, would be "ça t’arrive de X?". For example:

Ouah, ça t’arrive de marcher ?

Dis, ça t’arrive de mâcher ?

It will be used with the same sarcastic undertone as "X much" in English and means the same thing.

Davantage inspiré du sens que de la morphologie :

Sais-tu c’est quoi/ce que c’est que/ce qu’est/qu’est-ce que c’est (que)…
Sais-tu (même)(comment)…
Es-tu (même) capable de/d’…

…marcher/avaler/manger etc.