Since no one else has offered an answer I’ll give it a shot…
I would say the asnwer to all your questions are found in CrossFit. I know thats a simple answer so I’ll explain..
For starters eating-
Most people around here do Paleo or the Zone diets. Either one is a great choice. I personally do a combo of Paleo, Zone and low carb. Diet is a personal preference but whatever you choose, start off by eliminating as much processed food from your diet and cut out complex carbs…Just remember good nutrition and rest is essential to recovery and muscle growth.
Rest, skill work, CrossFit and Powerlifting..
All four of these will be found in how CF is designed.
Rest- CF has a 3 on 1 off routine. For beginners it is suggested to start with 1 on 1 off, after a month of so move to 2-1, then eventually 3-1. I would suggest, given your statements, to start off by just being consistent with your WOD’s. Pick either the morning or night and do a warm-up (which can be found on the beginners page) + the WOD. If time is an issue you can split up skill work and the WOD but certainly don’t do two WOD’s in a day starting out. That will most certainly lead to over training. Get to the point where you’re doing them more often then not. Just by doing the WOD’s you’ll improve on this..“I will be honest I have been on and off again with CrossFit. Mainly because I am weak at cardio,muscle endurance, and gymnastic skills.” A vast majority of people who’ve never done CF in their life fall into this category. It’s OK.
Skill work can come in your warm up or after or before the WOD. If you struggle with a movement, work at it. Grab a PVC pipe or broom stick and just practice the movement. Heck this can be done while watching TV. CF is Form > Intensity > Weight. Get form down first, add intensity and then add weight. I have struggled with this and sometimes get this order mixed up.
I assume you mean strength training. Well, if you follow the main site WOD’s that are scaled here there are enough “strength” WOD’s that come up in the cycle to help in gains for the major oly lifts. In fact, most WOD’s contain some sort of powerlifting movement. Whether it be cleans, dead-lift, squats, snatch, bench press etc. You’ll get work in them all. After doing the WOD’s + skill work for a at the very least 6 months, you can think about adding additional strength work to your routine. Every first time crossfitter has asked, “You just do the WOD’s and that’s it?” Give it six weeks and you’ll understand why.
Hope this helped