R.R.
If you always carry him after he's fallen asleep he won't learn to go to sleep on his own, I found that out with my first son. Start with naps, to get him comfortable with the crib. Lay him down when he's almost asleep or tired, make sure he's comfortable and leave. When he cries go in after 5 minutes or so, if he's sitting or standing gently lay him down, don't pick him up, but talk in a quiet, soothing matter-of-fact voice, and rub or pat his tummy or leg to calm him down, tell him it's time to sleep, that you love him and leave. You may have to repeat this many, many times, so don't get discouraged.
Also, darken his room with blinds or a shade, and have a fan going for white noise for naps and bedtime. Establish a calming after dinner bedtime routine with a bath, rubdown with nighttime lotion, a story or two, no roughhousing, tickling or excitement. Make sure he has a lovie of some sort to snuggle with to help him self-soothe to sleep and back to sleep. Do whatever relaxes him for sleep. Keep his routine as consistent as possible. It may take awhile for him to adjust so hang in there!