Good question! First of all, one of the primary definitions of sin is the breaking of God's laws. Whether or not you think his laws are fair is besides the point. Just like in the human world, ignorance of the law is no excuse.
Now consider this analogy. Say you are a fine upstanding member of the community who gives to charity and does volunteer work and helps little old ladies cross the street and you always obey the law. But one day you are driving your car and not paying attention and you run a red light.
You come before the judge and tell him all about how good you are and how you just made a mistake. The judge can't declare you "not guilty" because he is sworn to uphold the law. In the same way God cannot declare a person "not guilty" if they break one of his laws because that would make Him a liar when He gave us the laws.
Now, have you ever stolen something even if it was something small like a pen from work?
That would make you guilty of being a theif.
Have you ever told a lie?
That would violate God's law against bearing false witness.
Have you ever used the name of God or Jesus like a curse word?
That would be the sin of blasphemy.
Have you ever looked at a woman with lust in your heart?
Jesus said that anyone who looks at a woman other than their wife with lust has already committed the sin of adultery in their heart.
God says that anyone who breaks even one of his laws has to pay with their life. It may sound harsh, but God doesn't need anyone's money or for them to do anything for Him to make up for their crime. He is in charge and He says that the penalty for sin is death.
So if you were to come before Him and be judged according to his laws what do you think He would be compelled by his perfect nature to give as a verdict in your case?
So now you have to a decision to make. Is it more important for you to spend a comparatively short time here on earth indulging yourself in deceptive pleasures, or is it more important to have the assurance that when you die you won't spend eternity in hopeless damnation?
Sure, sin is fun for a time. But when you come to Jesus and receive God's Holy Spirit you will start to have a changed life over time. You don't have to give up sex, you just find a wife. You can still have a drink, you just can't live your life as a drunkard.
It may sound dead and restricting but over time a person just loses their old desires and they are replaced with new activities that don't lead to hangovers and sexually transmitted diseases and being arrested and stuff like that.
God has already paid your sin debt by sending Jesus to die in your place. All you have to do is accept this gift by faith.
I pray that you will find a good local church, show up and listen to the gospel message, and let the Holy Spirit draw you to new and eternal life in Christ in whose name I pray, Amen!