Usage of 'out of my reach'

Hi,

Can I use ‘out of my reach’ to mean ‘beyond my understanding’?

Also, can someone please suggest a couple of other expressions/idioms that mean ‘out of my depth’?

Hi,

‘Out of my reach’ can mean literally that I can’t touch it/hold it/grasp it or it can mean figuratively I can’t aspire to something or attain something as in: I tried to pick the apple at the top of the tree but it was out of my reach or That sort of house price is out of my reach.

As for other expressions: It’s beyond my ken or I’m floundering or You’ve completely lost me there.

Alan

Hi,
Could you please tell me what “out of my depth” mean?
Many thanks
Nessie