Dodge Van Battery Replace/Remove

How Hard Is It To Replace The Negative Battery Cable? It Has Three Wires Coming Up To The Connection At The Terminal.

Vehichle Died. Possible Alternator And Bad Battery. Changed Battery , But Vehicle Now Turns Over But Will Not Start. Is There A Reset Relay...

When I Go To Start The Van It Cranks A Few Times Then Acts Like The Battery Is Dead I Replaced The Starter And Battery Nothing Changed It...