How to do prune this?? Should I prune it? How do I get this Japanese maple leaf to be a beautiful bonsai like it deserves?

Thank you!

That maple is just a young seedling and needs to grow in the ground for a few years before even thinking about leaf size.

Br
Magnus

So do nothing and let it grow taller until it has more established roots?

By putting it outside, into the ground, letting it grow for several years, while studying some general horticulture followed by specific bonsai culture.