I had a bunch of friends get braces and the one unanimous thing that they ALL complained about was when they tightened the braces to straighten your teeth and that it would hurt like a motherfucker and be sore for like a few days after.

HOLD ON, I will aquire my Brother who has had braces!

Okay, so I used to have braces. Oragel is going to be your best friend for when you first get them on, and when you get them tightened.
First off, you HAVE to brush your teeth soon after you eat no matter what you eat.
Do not eat crunchy or chewy things.
(No gum etc)
Eat softer things and try to cut everything you eat into the smallest pieces you can manage. It will help so the food doesnt get too stuck in your braces.

If you want to eat something like apples and pears, take the time to peel them and cut them into small cubes. If you dont, it will either get stuck in your braces or snap a bracket off. (Orthodontists hate when you snap a bracket off)
Even mashed potatoes can make a bracket come loose so dont worry.

There are these weird things in the dental isle at stores you can find interdental floss brushes ( https://imgur.com/b7ZUi1E ), and electric toothbrushes. Those will also be your best friend. Trust me, get a bunch of those weird floss brushes, it makes it easier to clean in between the brackets that you cant get with a toothbrush.

You WILL get stuck to random objects such as a blanket or pillow or hoodie sleeve. Specially if it is fluffy and you sleep with your mouth open, (or if youre an idiot like me who manages to smack himself in the face with a hoodie sleeve and have to acquire help to remove it from my face.)

The wire that will be used to hold the brackets in will sometimes be too long and dig in to the sides of your mouth, or even the brackets themselves. The orthodontist will give you wax pieces. Use bits of the wax to place on top of the offending pain module and it will make it so it dont tear up the inside of your mouth too much. it takes a bit for the mouth to get used to having the braces on.

If a bracket does fall off, call the orthodontist ASAP and schedule an appointment. Sometimes they will just be hanging there on the wire, dont play with it. but if it falls off falls off, then make sure to put it in a baggie and take it with you to the dentists so they can put it back on. If you dont have it, make sure to tell them on the phone when you call so they know ahead of time to prepare a replacement. Sometimes accidents happen and you will swallow a bracket (doesnt happen too often, but it does indeed happen)

When it is time to get braces off and you have to wear a retainer. ALWAYS wear it. even after they say you can stop. why? because your teeth WILL shift out of place. (Another two people i know who did the same mistake i did and their teeth shifted back as well, so make sure to wear that)

I may have forgotten a few things since it has been a few years since i had them. I do say they are super worth it for sure. The orthodontist will give you a run through of dos and donts as well as give you a guide on how to take care of them so that will help too.
If you have any more questions, I am more than happy to answer them for you :)
Hope this helps!