No worries! Very happy to help, it's what we're here for.
You want to upgrade the tank size as soon as possible, don't wait for them to get big first, since by then it's too late, and it may stunt their growth. Mollies are one of my favourites! The black and dalmatian mollies especially can get really quite big when given the space and food to grow. Mine reached an easy 4 inches in a 57g tank:
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This is just to give you an idea of how large they can eventually get, given the chance! This were almost 8 years old, so it took time to get this large, but the gold dust molly behind them, the gravid platy in front, and the male guppy above are all adults! So the bigger the tank you can manage, the better really! Mine used the whole of the 57g. Bear in mind that they're shaped to swim, so they're an active fish that need space to explore. With mollies and a decent school size of cories, I'd recommend a 30g minimum, and it'll also give you far more options for other fish to keep!
Mollies and cories are fine together, I've kept them together too.
A reliable and accurate site for fish info is called Seriously Fish. They give all the parameters that the species of fish need, and include things like behaviour and compatibility, so you can see what sorts of fish would work (or wouldn't work!) with the fish you already have.
There's a lot of misinformation online, since anyone can write a blog or have a YouTube channel, so it's always good to have a reliable resource to be sure about what your fish will need!
Here's their profile on Black mollies (same info will apply to dalmatians)
www.seriouslyfish.com
And on bronze cories:
https://www.seriouslyfish.com/species/corydoras-aeneus/
Better to have at least some of the same species together, rather than a "pick 'N mix" approach. But in a larger tank you can mix different species together and they get along fine, since they're all peaceful and highly social. I have bronzes, sterbai's, black venezuelans and three adopted spotty cories together, and they're all social together - but they do tend to gather together with those of the same species when spooked or hiding out in their safe spots. Like the sterbai cories especially tend to stick together. So I'd suggest getting another two young bronzes now, so you have three together, then get three more once you've upgraded to a larger tank.
Ten gallons is really too small for bronzes, but if you're confident you can upgrade soon, and want to keep the one you have and have a school of them, then you could manage three young ones in a 10g as long as you keep up with maintenance and regular water changes! Bronzes can get relatively big and chunky, especially the females. But your singleton would be much happier with friends!
Here's some of my youngsters, after mine bred. Had 86 babies to rehome!
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