What is a force?
A force is a push or a pull.
A force is a push or a pull and the strength of that push or pull is given the units N (Newtons). If there is more than one force acting on a mass, the acceleration is given by Newton's 2nd Law:
#F_"net" = m*a#
Notice that since Isaac Newton developed the above law, the unit given to the magnitude of a force is also named for him.
I hope this helps,