I see a few problems with your thinking. The first one third of your post is just "woah, big things are sooo big, woah dude mind blown exact earth copy". Being this impressed with something opens you up to being gullible and think new-age. Magicians, clowns, parents try to get children into this mindset to sell them anything they want, be it santa or the importance of eating your veggies. If you get into this mindset, wait until it goes away and treat any ideas you got on it as if it was the ramblings of someone on LSD.
>But if the Universe isn't endless, what comes after the edge of it? WHAT IS THERE???
You are abusing language or thinking statically. If the edge of the universe is the edge of the universe, the question doesn't make sense, is invalid, is just language abuse.
If there is however something beyond the edge of the universe, it wasn't the edge of the universe after all. You were thinking statically. The actual edge is after this "WHAT IS THERE???" thing. This is the same mistake as calling atoms atoms - atom means "cannot be divided" but they can into quarks, yet people still call it atom, language is being stupidly static. If you say there is an edge of the universe and something beyond it, you are calling some inner layer the edge of the universe, you're being static. You need to find it a new name and call the thing that is outside of everything else the edge of the universe. You need to dynamically adjust the name of things, or you'll fall into language bullsoykaf like this.
We don't _know_ the big bang, it's just a theory as is an expanding universe and everything ever claimed by physicists. Be aware that when you incorporate anything claimed by physics as a field, you are doing a game of "what if". It's good for practical purposes and short-term simple predictions.
I won't even bother with the big-bang simulation part, it's just more of the impressed mind-blown shenanigans.