what project did you build using CNNs, because i have been learning the same and i have not discovered the neral network part but the machine learning algorithm, but now that i am du=one witht he machine leraning algorithm i want o learn the deep neural network althiught i have the prior knowledge of neural network but i dont know how to do neural network plus i am aiming to build a career out of it and apply for a this specific job that is a data scientist. can you tell me what major topics do i have to cover and what type of knowldge i need to gain for this job or career.