Triathlon?

I'm training for my first now. The tentative date is 7/22. Lots of building a base currently

I started with Sprints (500 yd swim, 12 bike, 3.1 run). Those where fun. A few swims where in a pool. That gave me the fever.
Then went to Olympic distance (1 mile swim, 24 bike, 6.2 run - these are approx. distances, each race varies slightly). That takes a slow guy like me about 2 hrs 45 min to complete. These are super fun. You have a chance to really hammer it. Pacing is important, but you can get away with pushing a bit more on the bike.
Then did the Kansas 70.3 half Ironman. I did this one with Hines Ward's transition area right next to me. He's the NFL player that was learning triathlon for some charity challenge. That was 1.2 swim, 56 bike, 13.1 run. This is my favorite distance.
Then did a 100 miler. That was 2 mile swim, 80 bike, 18 run. I trained that just like an Ironman. the run was brutal after mile 13.
Finally finished with Ironman Wisconsin 2016. 2.4 mile swim, 112 mile bike, and 26.2 run. 14 hours. I only cried twice on the run (true story). 6 months holding a solid base, then 6 months of detailed by the book training. Next to the birth of my kids, finishing that race was one of the highlights of my entire life.

The main thing with any distance is training consistency. Don't skip workouts and embrace the suck is what we say. Bike your ass off. Then when finished, bike some more. Run off the bike often (brick). Even if it's just 1 mile, get used to that feeling of running off the bike. And.....just do it. You'll learn on your own and meet local people at the races to help you along. Have fun!

I was going to do one this spring with my wife at the Texas 70.3, I can't get in the proper amount of training with my job so I will back it down to trying a Sprint first. BTW those Brick workouts are a big bag of suck. I did one a few weeks ago and did a 10mile bike sprint into a 2 mile run and I wanted to die!!!

Best of luck to you.