How to use “to say” and “to tell”

S + say + (that) + S + V…
He says that he is busy today.
Henry says that he has already done his homework.

But if after the subject has an indirect complement (which refers to the listener) and the linking word “that” , must use “to tell”.
S + tell + indirect object + (that) + S +V…
He told us a story last night.
He tells me to stay here, waiting for him.
To tell has also a direct complement. We use to tell when in stenses have the words:
Tell a story
ajoke
asecret
a lie
the truth
(the) time
Never tell a secret to a person who spreads gossip.
The little boy was punished because he told his mother a lie.