Samarendra, your last image looks like leaf miner damage. Leaf miners are not usually threatening to plants, but control can be needed to manage the really pronounced tunnels in leaves that can reduce crop health.
Management:
-Monitor plant leaves closely. At the first sign of tunneling, squeeze the leaf at the tunnel between two fingers to crush any larvae. Pick off and destroy badly infested leaves in small gardens.
-Make sure to maintain plant health with organic fertilizers and proper watering to allow plants to handle pest damage.
-Use yellow sticky traps to catch egg laying adults. Cover soil under infested plants with plastic mulches to prevent larvae from reaching the ground and pupating.
-Organic neem oil will break the pests’ life-cycle by preventing larva from reaching maturity. Neem oil may also have repellent qualities and interfere with egg laying activities. (https://www.planetnatural.com/pest-pr...)
If possible, could you please share a more clear photo of the red insect on the leaf? It seems to be just out of focus and hard to make out the detail of it about 7 years ago.