A being that has always been and will always be is hard on the human mind but even we have a concept of INFINITY. Number theory. Infinite sets. No smallest number, no largest number. Time has not beginning nor does it have and end.
We have two choices and only two. Either "Something" has always been OR, before something, nothing was. Since your statement acknowledges that something cannot come from nothing, then something has always been.
Psalm 90:2 reads:
"Before the mountains were born Or you brought forth the earth and the productive land, From everlasting to everlasting, you are God."
As something has always been and as Romans 1:19,20 quoted earlier notes ".....For his invisible qualities are clearly seen from the world’s creation onward, because they are perceived by the things made,..." Or his creation.
That is, this something that has always been is "Intelligent", a spirit person. His 'qualities' are seen in his creation. Wisdom, Power, Justice, Wisdom.
It is also a fact that one can, and many do, CHOSE not to believe or if they do, not place faith in him. 2 Thessalonians 3:2 makes this point:
".....for faith is not a possession of all people."