What exactly is "the gospel"? I know that it means "good news" but what does that mean?

it means... you don't have to suffer in Hell for all eternity... Jesus took your place on the cross and paid your sin debt...

In other words..if you dont want to serve Jesus...He will burn you alive in unspeakable agony in a special place HE created for people like you..

SO BOW OR BURN FOREVER...its a free will choice....

This is like a couple hour teaching.
Basically, Jesus came to live out God's Instructions perfectly without all the Jewish laws added. And lived them out the way they were meant to be-with the heart- not just the act of obedience.

He taught from the Torah and the Prophets. He worshipped in Spirit and Truth. He died for us, so that we don't have to spend an eternity separated from God's presence.

The punishment for sin is death.
Sin is transgression of Gods Instructions

He paid our debt if we believe that He is Messiah the son of God who is also God!

It means the truth.

"The Gospel" is this, JESUS CHRIST WAS BORN, DIED ON THE CROSS, SAVED YOU FROM YOUR SINS WITH HIS BLOOD, AROSE FROM THE DEAD, AND SITS AT THE HAND OF THE FATHER. We can not live the perfect life, but when we accept the LORD JESUS, he covers our sins. This is the good news! JESUS SAVES!!