What's your narrative about how the existence of the universe came about? How can something just randomly appear out of nowhere? I guess the universe has to have already existed forever

Let's discuss it over a cup of tea. Can you fetch my teapot? It's in a solar orbit between Earth and Mars and so small that it's impossible to see from Earth even with telescopes, but it's totally there (trust me bro). If you can't find it, you're just not looking in the right place.

Many people, much more intelligent than you or I, have philosophised about the lack of human understanding in particular areas. What you are doing is attributing the birth of the universe to the "god of the gaps". Your only evidence to support your conclusion is a lack of evidence to the contrary, and that is not a strong foundation to any argument. Any assertion that is made without evidence should be dismissed without evidence (see Hitchens' Razor). I could just as easily claim that the entire universe and all living things came to existence last Thursday, and all evidence to the contrary came to exist that way as false evidence (see omphalos hypothesis, last thursdayism).