What is the meaning of life?

Is there an inherent meaning to life? Is there a predetermined purpose to life? Many people would argue there is. This week I was introduced to a video by the William Lane Craig related organisation Reasonable Faith. Here they argue that Atheists can not lead a life that is both 'happy and consistent'. Reason being that, if God doesnt exist, humans aren't created and thus there is no purpose to life. As this video raised some questions, I decided to make a response to it.

Why is an inherent purpose in life needed?

One of the objections they seem to have is "if Atheism is true, humans are not designed and they don't have a an inherent purpose in life" There won't be a reason as to why we exist. My question to that is "why is that needed? Why is this a problem?"

When there is no inherent purpose in life, this allows you to give meaning and purpose to your own life. You can find something to be passionate about, without the fear that a divine being doesnt permit it, and pursuit happiness with that.

It also begs the question, if there is an inherent purpose in life, what would it be? In discussions with many theists over the years, I've gotten the distinct impression that they feel their purpose is to 'praise God'. I'll be honest with you. I have no idea what that entails. I also have no idea how that would improve ones life or eternal afterlife.

I know, I know. Question begging is a fallacy. Presupposing that 'improvement of life' is a necessity or desired does begs the question why that is. For this I can oly refer to nature.

The human species is a curious, exploratory species, always trying to gain more knowledge. It's in our nature.

It doesnt just make our lives easier, we do find purpose, meaning and happiness in it. Shouldn't that be just enough?

Why does one need an inherent purpose placed on them, by another entity?