Q.Sick plant
Can you identify what is wrong with my plant? Some of the leaves are very light yellow in color and are turned downwards. Some of the tips of the leaves are brown. I water it at least once a week.
Let's assume that you fertilize container plants as required, that they get the appropriate amount of sun and that your container has drainage holes. They depend on that since they are not grown in real garden soil. These leaves looks like they are getting old, have done their part and are "senescing". They can be peeled or cut off. The plant as a whole looks healthy. Here is an article on care of pothos: https://www.gardeningknowhow.com/houseplants/pothos/pothos-plant-care.htm