What is the main difference between constitution and the declaration of independence

The Constitution is is document that was made up of rights, laws and amendments to help set  the new country ( 13 colonies or America). The Declaration of Independence was a document signed to declare that the 13 colonies sever their ties of political connection to Great Britain, they wanted to rule independently from the mother country.

bibliography and citations to credit the sources hope this you if not my deepest of apologize ^w^

2018 means 2018 ce or common era

there have been other eras too including bce, which included way more years.