Take it from a Marine right here (I assume it's the Marine Corps because Marine only call basic training boot camp unless that moniker changed) good luck.
Prepare to shit yourself in fear and frustration for the next 3 months. Somewhere around the first month you pretty much get used to the constant yelling an the IT (Incentive Training). I remember at one point during boot camp I got IT'd for roughly an hour and a half for wiping sweat off of my face. They have a strict no face touching policy in boot camp.
First month you go through the regular bullshit of getting broken down and feeling like an utter piece of shit no matter what you do. Plus you get to PT constantly so you get that fun on your back. You do some MCMAP which I suggest you don't use in the real world unless you want to get your ass kicked. Then you drill constantly which is fun minus the stress behind it. Some people are really good at it and others just don't know how. I remember one recruit where he was forced to be "sick" on the day of our initial drill evaluation. Then you go through a Swim Qualification that last for a whole week which really isn't that bad minus the yelling. You take some basic Marine Corps history classes, "Who is the Grand Old Man of the Marine Corps? Archibald Henderson" Go through rank structure fast and your general orders which, by the way, I forgot. I only remember the 5th one because it's the best one, "To quit my post only when properly relieved."
You then roll around to month two where you learn how to use your rifle and go through table's 1 and 2. Known Distance and Close Quarters. While you are there you are introduced to the hike's or, as we like to call it, humps. They kill you especially if you are in San Diego. But if you tough it out and not be a pussy you'll feel accomplished...or broken whichever comes first. You do about three of them at boot, but seem fairly easy now that I think about it. I remember during my 8 mile I didn't have a waist strap so I had all of that weight on my shoulders which fucking killed me. My feet were damaged beyond belief and I nearly gave up before we reached the end. But I made it surprising my Drill Instructors and the other recruits because I was seen as "weak". I did all of it and made it.
The last month you go through some more PT and your final drill. You start getting fitted in those fine uniforms and you get your named tags. The ones that say U.S. Marines on them. You feel proud to have them, but you are not out of the water yet. Because now you get to do the Crucible. 3 Days with little food, lots of humping and physical activities. I made it...we all made it. For us we had to do a final hump. A 10 mile up what is called the Reaper. Its a huge fucking hill that you climb but once you make it you hit jackpot. Honestly the hump back was harder than the hump there.
But in the end...you make it. You make it to that Eagle, Globe and Anchor celebration. The Drill Instructors that gave you shit all those three months walk right up to you and hand you that emblem. Something that you have been striving for ever since you first put your feet on those yellow footprints. Some cried because they worked so fucking hard to get it. Some harder than most because it was necessary to bring that man out him. When my DI, SSgt Brusches (I know I spelled his named wrong) walked up to me, placed it in my hand and shook my hand I couldn't believe it. I'll never forget what he asked me, "So what's your MOS going to be?" "Infantry Staff Sergeant." I replied. "Gonna kill some bad guys huh?" "Yes Staff Sergeant" I choked out because I was so happy and tired. I remember seeing the tape and it was like a sea of swaying Marines tired as hell. Then you get that awesome breakfast and chow down as much as you can in your gullet. You graduate and it's on to your Marine Corps career.
Now the fleet is different and you'll catch a lot of shit just for being a boot. Don't be a fuckup and always assert yourself. People will respect you for it, but it'll be tough.
Also, I hoped you joined Infantry because all the other MOS's are pog pussies.
I joke, but seriously, Infantry is the best.