The following images are of some reactions amides undergo, with an explanation to show how these compunds react in general.
Hydrolysis of and amide in acidic conditions.
A positive H atom attacks a lone pair on the Oxygen in the amide, giving the O a positive charge. A water molecule attacks the C atom forcing the double bond to become a single, neutralising the charge on the O. The attached water molecule has a positive charge on the O now, so loses a H to neutralise. A positive H atom attacks the lone pair on the N atom, giving it a positive charge. To neutralise, a lone pair from the O comes down forming a double bond with the C again (so there is again a positive charge on the O). This forces the bond from the C to the N to break, with the elctrons going on to the N neutralising it as a stable compound. The double bonded O now loses its only H, neutralising the charge leaving a stable carboxylic acid.
This reaction can be done in basic conditions aswell
Amides react at the C atom, when attaching new groups onto the structure. However, the lone pairs of electrons on the O and the N are easily attacked by positive H ions, allowing reactions like the one described above, to happen.