Historically, this order (specifically the version from 2017) established the rules for (MTO) for the Russian military. It covers:
Guidelines for providing food, fuel, and equipment to personnel.
There may be specific local or older variants (e.g., related to military education or health standards) that use the same number.
Which specific or year of Order 555 are you interested in generating a piece about?
There is sometimes confusion with FSB Order 547 or 555 regarding "foreign agents" or information security, though these are technically different agencies.