The gospel is the word of God. It is what is written in the Bible. The gospel is referred to as good news due to some many reasons a few of which will be explained here.

1. The gospel talks about the Almighty God. Its good news if anyone can tell about God that we cannot see but can see His mighty works. We can see His blessings and His words coming to pass as stated in His word.

2. The gospel is good news because it talks about man’s salvation. The gospel is the power of God unto salvation. It provides a way of escape for us to come from darkness to light from backwardness to forwardness. The gospel ensures we know how to escape from hell to heaven.

3. The gospel removes fear from our hearts. Perfect love casts out all fear. From the dominion of Satan to becoming people that have dominion. God talks about our freedom...

See details here https://newkokoro.com/2019/01/10/why-the-gospel-is-called-good-news/