Can you list an example or two of an infinitive being used as an adjective, and explain it?
"I've found something to read".
"This is not a very good way to begin".
"I've bought a great video to watch tonight".
In those three examples, the infinitive verbs are modifying the preceding nouns, "something", "way" and "video" to form the underlined noun phrases.
But please don't call them adjectives. They are verbs functioning as modifiers, not adjectives.