Don't call God a liar. I'm not sure God would like that.
The God of the Bible created the universe. The universe did not always exist.
You are entitled to your opinion.
It is not an opinion, it is a matter of exclusion.
Either the universe is eternal and always existed or it was created.
The only exception to that you carved out is if God created a universe (thus it did NOT always exist) that gave the appearance of being eternal (which would be a lie, or illusion).
It is not my opinion that the God of the Bible created the Universe - it is the description of God given in the Bible.
So.... there was a beginning.
It is not eternal.
In this beginning God CREATED.
There is no need to create that which has always existed.
As far as “Last Thursday-ism” you struck on why it is preposterous your very first try - it makes God out to be a liar. By suggesting the universe was created to mimic the appearance of being eternal - it is you who make God out to be a liar.