I have tried many things as well as looking things up, including some suggestions from this site. I need to know how to use the command
fill for Minecraft Education Edition 1.12.5.
Copied verbatim from the DigMinecraft website (first hit searching for "Minecraft Education Edition fill command"):
Fill Command in Minecraft Education Edition
In Minecraft Education Edition, there are 2 syntaxes for the
To fill a region with a type of block:
/fill <from> <to> <tileName> [tileData] [outline¦hollow¦destroy¦keep]
To replace one type of block in a region with another type of block:
/fill <from> <to> <tileName> [tileData] replace <replaceTileName> <replaceDataValue>
<from>is the starting x y z coordinate for the fill region (i.e. first corner block).
<to>is the ending x y z coordinate for the fill region (i.e. opposite corner block).
<tileName>is name of the block to fill the region.
<tileData>is optional. It is the data type or variation of the block if more than one type exists for that
<replace>will replace all blocks in the fill region, including air.
<outline>is optional. It will replace blocks on the outer edge of the fill region, but does not replace the inner blocks.
<hollow>is optional. It will replace blocks on the outer edge of the fill region, and replaces inner blocks with air.
<keep>is optional. It will replace only air blocks in the fill region.
<destroy>is optional. It will replace all blocks in the fill region, including air.
Replaced blocks will be dropped and can then be collected as if they were mined with a pickaxe or shovel.
<replaceTileName>is the name of the block that will be replaced.
<replaceDataValue>is the variation of the block to be replaced if more than one type exists for that