Yes, climate does change all the time and yes it is cyclic and yes it is affected by the Sun and all of that.No one has ever tried to deny that. No one has failed to take those natural cyclic variations into account.
The important question is what impact upon that cyclic change has been introduced into the system from the actions of humanity,most especially since industrialisation and urbanisation, and the consequences to the climate of that impact. So I am not sure who you are accusing of lying, and what it is you think that they are lying about?
As to your comment about China and its "one child, one family" measures that were implemented - Sorry, but I am unclear what it is you are trying to say. People-Scientists, and others- warned China right from the start what the possible consequences of such a policy were, but the Chinese authorities ignored those warnings, mostly because they feared the consequence of untrammelled population growth more. Its not as if the gender imbalance was unforeseen or anything.
And, as with all complex issues like this, that tends to be the problem - actions of governments and societies are dictated by balancing out relative risks of inaction or action. The major concern - and one shared by all of the worlds leading scientific institutions, academies, universities, reputable climate experts etc that I am aware of - is that the human contribution to climate change could prove to have catastrophic consequences for large segments of the human population in the not-too-distant future, unless we do something about it now.The action needed though is proving unpopular amongst some businesses, some sections of Government, and amongst many of the population, because the actions that are being suggested as being needed could cost more.