I have cuda properly placed now, had wiped it out and reinstalled it again.
So during Cmake compilation it detects libcudnn.so and says libcudnn7 or above required even though I have both libcudnn.so and libcudnn.so.8 in /cuda/lib64. To circumvent this I  changed this from a fatal error to a warning in cuda.cmake and cmake runs fine.
However running make throws the error fatal error: torch/torch.h: No such file or directory  #include <torch/torch.h>
What could be going wrong??.
CMakeLists.txt is -
cmake_minimum_required(VERSION 3.16)
project(Pytorch_c__)
set(CMAKE_CXX_STANDARD 14)
set(CMAKE_PREFIX_PATH "/home/atharva/torch/torch/")
find_package(Torch REQUIRED)
add_executable(Pytorch_c__ main.cpp)
target_link_libraries(Pytorch_c__ "$(TORCH_LIBRARIES")

and cmake output is -
-- Caffe2: CUDA detected: 10.2
-- Caffe2: CUDA nvcc is: /usr/local/cuda/bin/nvcc
-- Caffe2: CUDA toolkit directory: /usr/local/cuda
-- Caffe2: Header version is: 10.2
-- Found cuDNN: v?  (include: /usr/local/cuda/include, library: /usr/local/cuda/lib64/libcudnn.so)
-- PyTorch requires cuDNN 7 and above.
-- Autodetected CUDA architecture(s):  7.5
-- Added CUDA NVCC flags for: -gencode;arch=compute_75,code=sm_75
-- Configuring done
-- Generating done
-- Build files have been written to: /home/atharva/CLionProjects/Pytorch-c++

TIA