How do cellular respiration and photosynthesis provide energy for an organism to function?

Well the sun gives the plant energy through the chloroplast in the chlorophyll which makes it run

Mitochondria produce atp, a high energy compound. atp is used for all sorts of enzyme-mediated reactions, such as making proteins/nucleotides/etc, certain compounds cross the cell membrane, muscles move, etc.  without this source of energy, a cell will die. it will not be able to repair itself, defend against pathogens, etc.

Then it is june the conclusion to the second sentence is just restating "if it is june then it is summer"