The first and easiest point is that intend is a verb and intent/intention are nouns. Intent/intention can be used interchangeably. They both mean things you plan to do. However, I would say we sometimes also use intent to show you really aim to do something. He ran with great intent. That means he is really putting extra effort in

Intend is a verb; intent and intention are nouns. Intent and intention are the same (in most situations). Examples: 1. I intend (verb) to go to college next year. I intend (verb) to quit my job next month. I intend (verb) to prove that I am a better basketball player than he is. 2. My intent/intention (noun) is (verb) to go to college next year. My intent (noun) is (verb) to quit my job next month. My intent/intention (noun) is (verb) to prove that I am a better basketball player than he is. 3. He had good intentions (noun, meaning what he hoped to accomplish), but things turned out badly.

Intend is a verb and the others are nouns. I intend to win. Intent and intention can be interchangle at times as John said, but intent is more formal, less used and sometimes for law purposes, examples: from oxford thesaurs: she denies possessing the drug with intent to supply. he was charged with wounding with intent