Q.Cedar
I have two healthy Cedar at my backyard but I just notice yesterday that some part is turning brown is this a sign that my cedar is infested with that insects

Browning of needles or shoots could be environmental stress or more serious issues.
These links will help you access the tree.
https://www.gardeningknowhow.com/ornamental/trees/cedar/growing-cedar-trees.htm
http://www.clemson.edu/extension/hgic/pests/plant_pests/shrubs/hgic2056.html