The kingdom of heaven is at hand. What should we do?

In those days came John the Baptist, preaching in the wilderness of Judaea, and saying, Repent ye: for the kingdom of heaven is at hand. Matt 3:1&2

From that time Jesus began to preach, and to say, Repent: for the kingdom of heaven is at hand. Matthew 4:17

There were present at that season some that told him of the Galilaeans, whose blood Pilate had mingled with their sacrifices. And Jesus answering said unto them, Suppose ye that these Galilaeans were sinners above all the Galilaeans, because they suffered such things? I tell you, Nay: but, except ye repent, ye shall all likewise perish. Or those eighteen, upon whom the tower in Siloam fell, and slew them, think ye that they were sinners above all men that dwelt in Jerusalem? I tell you, Nay: but, except ye repent, ye shall all likewise perish. Luke 13:1-5

Forasmuch then as we are the offspring of God, we ought not to think that the Godhead is like unto gold, or silver, or stone, graven by art and man’s device. And the times of this ignorance God winked at; but now commandeth all men every where to repent: Because he hath appointed a day, in the which he will judge the world in righteousness by that man whom he hath ordained; whereof he hath given assurance unto all men, in that he hath raised him from the dead. Acts 17:29-31

The kingdom of heaven is at hand. What should we do?

Repent: Change your mind. Turn away from sin and turn unto God. Believe on the Lord Jesus Christ and thou shalt be saved.