1- my grandfather can draw a lot of hand-drawn letter,

my grandfather has made a lot of hand-drawn letter 

或

my grandfather have drawn many pictures on letters

2- it is a terrlific,he painted,many writers, earthquake relief, hand-painted seal film star....

it is terrific! He painted pictures of many writers, scenes of the earthquake relief and he also painted some film stars on seals.

哇你爷爷的作品真是超赞！