Howdy venymae
I only have bantams, no standards.
My gals do not like pellets so they are on organic coarse grain layer mix which is not bantam specific. If they did like pellets, I would buy them bantam sized ones or ensure that the larger ones are broken up a bit.
When I purchase oyster shell for them, I buy the bantam sized.
Because mine fly like bricks their roosts are lower than what you would probably have for a standard.
Because they are smaller, I am careful with regards possible predators as things which do not normally bother standards may be a threat to bantams, especially small ones; eg. Crows are a problem in my area.
As with anything chicken, there are always exceptions to the rule but in general, bantams have the same requirements as standards, just in proportion to their size. They are cared for and raised pretty much the same.