Since you originally placed this question in the “Karl Marx” section, part of my answer to this will address issues raised by Marx. The other part will be personal.
Personally, religion is not important to me. Although I was raised in a religious household, I have not been religious myself since I was a child. In large part, this is because I do not have faith in the leaders of any organized religion. It seems to me that most religions are run by hypocrites who are partly or mostly in it for their own gain. I have a hard time believing that I should go to a church and listen to someone who is no better than me tell me how I should live.
Marx assumed that religion was important to most people. He said that the ruling classes used it as the “opiate of the masses.” That is, they used it to keep the masses of people drugged so they would not realize how badly they were being abused. Today, I do not think religion can be used in that way in most Western societies. Most Western countries have moved away from organized religion. Therefore, I do not think that religion can work as the “opiate of the masses” in most modernized countries today.