Help with navigating the Atlanta Airport?

I have a flight coming up in a few days and I've never flown on my own usually my parents handled the check-ins and baggage, the last time I flew I was in middle school and now I'm an adult. I'm a bit nervous about doing it on my own so I'm trying to get ahead on the matter to be prepared.

My first issue: I'm not really sure where to tell my Uber to park for me? Like my itinerary doesn't inform me of my terminal (if that's where I'm supposed to go to check-in?) and I even looked up my flight number. It just says Terminal N but there isn't a Terminal N on any of the maps for the airport nor does it really pull up on google. It's just showing A-E, T, and F.

Second issue: When I arrive at the airport where do I go first? Check-in? How do I check-in? Is it a kiosk or a person? I keep seeing people say I can do both but then I see videos of kiosks? Then it says I need my itinerary, plus my ticket, and tag for my luggage but then I see it only says I need my confirmation number, my ticket, and tag for my luggage? It's really confusing and over-whelming as all hell.

Third issue: When I check in (It's Southwest Airlines) do I need to do it again at the next airport I change planes or should I be good to go? I saw that mostly I should be okay but I'm not sure.

Anyone who's a frequent flyer from and to Atlanta that could calm my anxieties would be highly welcomed and appreciated!

Uber:
Often car services have a place they have to use. Last I saw, Atlanta happens at the general pickup area though. You can ask someone at the airport and/or check the Uber app when asking for a car. If the airport controls where this can happen, the app will tell you where to go. If the airport doesn't control this, then just get to the arrivals pickup area and order your Uber. It'll be a 5-10 min wait in most cases.

Check-in:
There are different methods. Given you are on SWA, I highly suggest you check-in via their app or website as close to 24 hours in advance as possible. SWA does not assign seats. You get to board and pick a seat according to the order you check in. Don't wait until the airport to do this.

If you are not checking in a bag (thus only taking carry-ons) and have already checked in online, then you don't need to check in at the airport. Just use the boarding pass on your phone and head straight to security.

If you are checking a bag or want a boarding pass printed, then go to SWA kiosk or counter. Put in the info they ask for in the kiosk. It should print a tag for you luggage and also boarding passes. You then take it to the counter.

Never be afraid to ask someone or just go up to the counter and get things done there. Just tell them you're trying to check a bag and haven't flown as an adult. They will help you.

Layover Process: (assuming domestic flight)
Once you've checked in, you don't need to do it again. When you check in at the start of your travels you are checked in for the entire way to your destination No need to go through security again. You will have been given printed boarding passes to your next flight when you first checked in. (or they'll be on the SWA app.) If you have a round trip, you will obviously have to do this process again when going home from whatever airport you're at.

In general, don't be afraid to ask. Give yourself a little extra time than they suggest. Follow signs and check the departure boards for updated gate and time information.

There's a Terminal North at the domestic terminal.

The drop off is likely to be outside the domestic terminal.

Leave plenty of time to find where you need to go and to check in if you haven't done it online beforehand.

You tell the driver that you are flying Southwest. There are plenty of signs that tell drivers where to go.
You get out of the car and follow the signs to Southwest. Go to a kiosk or the counter. Since you don't know what you are doing, just get in line and use a real person (although there are usually employees walking around helping people use the kiosk).
Since it is Southwest, don't forget to check in online EXACTLY 24 hours before your first flight. If you don't, you will probably be boarding group C and end up in a middle seat. If you have a bag to check, you can still do that at the counter at the airport.
After all of that, go through security, get on the train to the right concourse, get off, and follow the signs to the gate.
When they call your group, get in the line under the right number.

Since you are flying Southwest, you want to check in online exactly 24 hours before departure. That's how you get your boarding order and how you will choose your seat. Southwest does not assign seats.

Your Uber driver will just need to head to follow the departure signs at the airport, and will stop at the one for Southwest. They are used to that - no big deal.

Go inside and take your bags to counter or kiosk to be checked and dropped off. It's a simple and straightforward process.

You will have your boarding passes for both flights that day. You will not need to check in again.

Thank you everyone for all the help! It really eased my anxiety. Ya'll are all wonderful and I wish I could award you all best answer. Bless 💖

Jesus! Its not that serious.