Given your level of concern and evident inexperience with self-loading rifles, I suggest that you start off with something less complex such as the straight blow-back operation Ruger 10-22, .22 LR semiautomatic rifle. Gain knowledge and understanding of self-loading systems as you continue to develop your safe firearms handling techniques and marksmanship skills.
If, on the other hand, you believe that you are ready for a .223/5.56mm rifle, then I suggest that you will find no easier rifle to get up and running than the LTAC Raven. All you should have to do out of the box is adjust your Gas System to "balance" or optimize the rifle's operating system for your particular ammunition. It is not a complicated process, with full written directions provided by Lockhart Tactical on the website. Provided you can read and follow written instruction, you should encounter no difficulty with this process. Aside from that, all of the initial teething problems with the Raven have now been addressed. The rifles all ship with the Gen 2 Bolt-Carrier and new, inspected barrels. You should therefore encounter no legacy issues, but even if you do purchase a New/Old Stock rifle instructions for getting up and running are provided in the comments of this discussion thread and in the FaceBook "Raven Owners Group - Official" on that social media site. You should have no trouble whatsoever if you educate yourself to understand the operation of the internal or "direct impingement" Gas Operating System that the rifle employs.
Best of luck, whichever way you decide to go!