What is the Fill command on Minecraft for Xbox One?

Az
2

I would like to replace certain blocks. (making a big white flower blue without changing other blocks, for example)
I can't get the command with (/ fill xyz xyz snow replace wool) to replace snow blocks with wool or other things. I also do not know how to delete a staked area. Can someone help me there?

co

Deletion can be written instead of wool, Air.

Gu

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