1.They're is the conjunction of they are
There is like location ex. The dog is over there
Their is associated with a person ex."her taunts had lost their power to touch him"
2. You would use an if there is if the next word begins with a vowel sound and you would use a when the next word begins with a consonant sound
3. How you would use the word to is saying something like I'm giving this to someone how you would use too is like saying this is too much say they add an extra o and two is the number so that is easy to memorize hope I can help!
My perfect day would be when I wake up having breakfast in my bed with my favorite movie and then put on the most comfortable and beautiful clothes I have, go out with my friends. When I get home, my family has prepared my favorite food for me, but to make the day perfect they cannot say no to anything or scold me. At night, have a sleepover with my best friend and stay up until dawn.