Normalization from UNF to 3NF

Ok, makes sense. In what step do I separate the ItemCategory into its own table?
item category

I don't want to constraint a department to only one admin, so it's a mistake too.

Can someone also please comment on the earlier NFs? I need to understand the step-by-step process. Or if someone can show me how they would do it from UNF -> 1NF -> 2NF -> 3NF, that would be extremely helpful.

Thank you.