Keep in mind that all the signage when you are driving there will just say "Magic Kingdom", the road signs won't mention the TTC, if I recall correctly. You'll park, then walk with the rest of the crowd (or take the parking shuttle, if that's running when you're there) up to the security area. Once you're through security, you'll be right in front of the ticket booths where you should be able to pick up your tickets.
Then once you pass the ticket booths, you can go either to the ferry boat to the left or the monorail straight ahead. I always felt like the monorail was faster than the ferry, even if there was a long line, as long as the trains hadn't stopped entirely because the ferry took so long to load and unload, but I don't know if that's still accurate with the social distancing systems in place. Sometimes they'll also have buses going from there to the front of MK as well, but I think that's only if the monorails aren't running for any reason.
Once you get off whichever transport you pick, you'll be at the entrance to Magic Kingdom. Keep an eye out for shorter entry lines along the row, as the crowd doesn't always disperse evenly. There is another ticket booth way off to the far right, but your wait should be shorter back at the first one because there are more booths there. But if you missed that one or if anything goes wrong at the entry stall, you would then go to the one on the far right.
For the other two parks, you'll just drive following the signs / use your GPS to get to HS and DAK (don't get thrown off by signs for Animal Kingdom *Lodge*). At those ones, you will park, go through security, and go straight to the entry stalls - the ticket you pick up on your first day should apply to your whole visit, so you won't have to go to another ticketing booth.
One final, important note: Every day, make sure you know the parking lot name and the row number where you parked so that you can find your car again at the end of the day. This is easy to forget, especially if you find yourself walking diagonally between cars instead of walking to the end of your row and then following the main road, but it's really important to remember because the parking lots are *huge*. Take a picture of the row makers, write it down, make it a game with your family for everyone to track the parking spot and then be the first when you leave to call out your parking location or whatever else you need to do to make sure you remember, because wandering aimlessly hunting for your car at the end of your day when you are already tired is absolutely no fun at all. If you do forget, you can track down security or a parking attendant who will help you figure out approximately where you were based on what time you arrived, but you don't want to have to get to that point.
