I did my first triathlon at age 50 and it was a blast. I trained for 5 months and it was just a sprint with a pool swim. My only goals were to complete it and to not be the last one across the finish line. I accomplished both.
Everyone here has given you great advice. I would also suggest that you read and do research. Your First Triathlon by Joe Friel is a good resource and has a good training plan to follow. Another suggestion that helped me was to go to a triathlon and watch at some point during your training.
It sounds like the swimming and biking won't be a problem for you. If you are doing a sprint triathlon, the run is usually a 5k and you could run/walk or just walk it if you had to.
Of course, you have all the ladies here at TE for help and support!
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