If you’re carrying him, that’s actually perfectly fine:) his neck support should be good by now. You can actually use a baby carrier and face him in front. That should be more comfortable for you too (less tiring than carrying). They like looking around them at this age, so it’s normal behaviour. When my LO was 3 months old, we took her out for walks in the carrier and she was in it facing the front. She loved it so much!