Is there any limit to give out merits for an individual? As a newbie can I still get merits or I need to be at least member to be eligible?
Yes, there is a limit to giving merit PER post. I believe you can only give a maximum amount of 50 merit point per post. Any rank can receive merit even newbie like you, getting one is easy if you're doing quality post and helping others with constructive and informative replies assuming a "merit source" notices you.