How to wake up MacBook Pro with external display with lid closed?
Mouse or keyboard activity does not wake up the computer. Is there a way to do this without opening the lid?
He's right; clamshell mode will not work unless the Mac-top is on external power.
Wake-on-mouse was last seen in Snow Leopard, it's been keyboard-only for some years now.
If your Mac-top is one of the New Breed (ie. it has a T2 chip) you can only wake a sleeping clam-book with a directly-connected (can't be in a hub) USB keyboard or a previously-paired Bluetooth keyboard.
Attach a charger and then you can wake it up with a keybord or mouse.