When you are a newbie to learning Korean, it is difficult to use a dictionary to look up things you do not know.
When you learn a bit of the grammar, you can better understand how to look up things in the dictionary.
For example, you will look up the infinitive of the descriptive verb. Then you can convert that to adjective form.
Here is an example. If you want to find the Korean word for delicious, you look for ‘to be delicious’ 맛있다 and then you can change it to adjective form 맛있는. See BusyAtom’s Lesson on adjectives.