CHOOSE YOUR WORDS

Every One vs

Everyone

There is often confusion over every one and everyone.

Every One
Every One (two words) can usually be substituted with each one. (In this expression, the word every is an adjective which modifies the indefinite pronoun one.) Try substituting the every one in these examples with each one:
•    Every one of those ideas is valuable.
•    I want every one of those picking up before lunch.

Everyone
Everyone (one word) is similar to everybody. (Everyone is an indefinite pronoun.)

Try substituting the everyone in these examples with everybody:
•    Everyone thinks of changing the world, but no one thinks of changing himself.
•    Everyone should be respected as an individual, but no one should be idolized.
•    Always remember that you are absolutely unique. Just like everyone else.

Source: grammar-monster.com