I have often heard that why would our religion be wrong if we believe in God.
Well let me start by saying that every person has a religion. Even the one who says I don't belong to any religion.
This is gonna be interesting...
Assume that you don't follow any religion, I will ask you four questions
If somebody came to kill you, do you think it is okay if you killed him? self defense?
Depends on the situation. If it was the heat of the moment and I killed them inadvertently in the process of defending myself - or if a situation arose, unlikely as it may be, where it was a definitely me-or-them scenario, then yes; It would be okay.
Is it okay to have alcohol?
Again, depends on situation. Is it okay for people to enjoy drinking alcohol in moderation (or without moderation, provided it's not constant). Yes, I believe it is. Is it okay to keep drinking when you're well passed the point of your brain being able to form sentences? Probably not. Is it okay to buy alcohol for a friend who is a known alcoholic? Definitely not.
Is it okay to have drugs?
Are these questions going to get specific or meaningful at some point?
Again, yes, in moderation. See above.
Is it okay to lie for a good reason?
Depends entirely on the lie and the reason. This is impossible to answer without being more specific.
Now I can make a thousand question in the list. The set of answers you provide for these questions is your religion. They form your beliefs by which you live your life.
That's not a religion - it's just a set of beliefs and opinions. Religions, by definition, are mandated systems of beliefs - usually supernatural in nature - which require adherence to certain set principles, practices, traditions and forms of faith and/or worship.
Now before you give answers to these questions and adopt them in your life, it is your duty to search and see if God already handed you answers to these questions.
Nope.
And since religions have major differences, there is only one true religion. Just like 1+1=2 ... You only have once right answer. And let's not forget that there are MAJOR difference between religions in the worshiping aspect. Not only in the do and donts.
So its our duty to search for this true religion that God gave us, and I firmly believe that God didn't leave each one of us to live by his standards.
This argument makes no sense. You assert that we all have our own, individual religion, then assert that there is only one true religion. I don't get your point at all. Pointing out that lots of people believe lots of different things and answer certain moral problems differently isn't an incredible, mind-blowing revelation. It's blindingly obvious. The question is how you go about determining that this was God's intent, or whether or not God intends anything or even exists in the first place.