I will differentiate imperative and Exclamatory sentences with the help of sentences.
word
Brush
Imperative sentence
Brush your teeth
Exclamatory sentence
what a cheap brush is it!
word
Window
Imperative sentence
Open the window
Exclamatory Sentence
How expensive the window is!
word
Flower
Imperative Sentence
Do not pluck the flower
Exclamatory Sentence
what a beautiful flower is it!
word
Garden
Imperative Sentence
Take exercise in the garden
Exclamatory Sentence
How wonderful the garden is!