Isn’t shellac/gel the same thing? …

this is a minefield!
I am super confused by the names tbh

I know gel nail polish and shellac (& gellac...& any other name brands have come up with) are the same. But is BIAB the same too?
Actual gel nails are the extensions (full or half cover tips) with the gel that comes from a pot (much more difficult to do than gel polish which is more like a reg nail polish application). Acrylic nails are more similar to gel nails bc you use a nail brush and the product is in the pot (either gel or powder) & you have to mold it into shape.
If you have tried the actual gel nails & don't like it, I know you said length was an issue, then a gel polish/BIAB just on your natural nail will probably be a great option.
I like to use gel polish when I want just short nails but then if I want to do nail art, I'll do gel nails with full cover tips.