I did the command /give Autumn225 minecraft:command_block 1 2 And i got a command block which in my hand had a gmod texture but when placed was normal and when i hover over it in my inventory, it said command block. And when i look at myself in my inventory while holding the block, the block is huge.

[Edit]: It seems this happens with all blocks, when i gave myself a log with the data tag being 34, it said the block was an oak log, but when placed it had the birch texture

In other versions of Minecraft, if you gave it a data tag that didn't exist, such as 34, it wouldn't give you a block and would give you an error.