Where do we come from?
According to the FIGU booklet Attacking questions from Japan... and Contact Reports 9, 236 and 251, the Earth has immigrants from several other star systems, including:
But also according to Contact Report 251 there are also immigrants from other planets within our own star system, namely Mars and Malona (which is now the asteroid belt between Mars and Jupiter).
The human lifeform also developed indigenously on this planet and mixed with the immigrants or extraterrestrials.
However, Contact Report 251 also states that the Sirius star system was colonised by humans from the Lyra, Plejares and Vega star systems who were themselves colonised by humans from the Waron star system of the Lyren galaxy which is 3,816,000,000 light years distant from the Sol star system. Therefore we can really consider our civilisation as being a mixture of indigenous Earth human races and human races that developed in the Nisan and Waron star systems.
The information regarding the earliest forms of human life in the Lyren galaxy is currently not available, but when considering the entire universe, around 39,000,000,000,000 years ago was when the first hominid lifeforms formed from which developed the recognisable human form.
Of course this is only referring to our physical or material life-form and includes no information regarding the human spirit. For that you are advised to read The Spiritual Teachings.