An adjective describes a noun: a person, place, or thing.
An adverb describes a verb, an adjective, or another adverb.
Below is a paragraph containing both adjectives (in italics) and adverbs (in bold) so you can see the difference.
“A scary witch stood behind me for a minute, waiting patiently before I crumbled. She was wearing a tall hat and holding a purple orb. I turned around before she put her pale hand forward and began to cast a spell over me. I ran away quickly, avoiding her petrifying curse.”