Conda install (Ubuntu 18.04) - Where to point LD_LIBRARY_PATH to?

Goal

I would like to run a muscle simulation demo found here: https://github.com/vcg-uvic/viper
One of their instructions is to set export LD_LIBRARY_PATH=/usr/local/cuda/lib64.
However, there is no cuda folder in local.
I would like to know to what path I’ve to set LD_LIBRARY_PATH.

Should be installed

I have been using CUDA for deep learning, installed indirectly when installing PyTorch through to Anaconda Python package manager.
I installed it with the following command: conda install pytorch torchvision cudatoolkit=10.2 -c pytorch.
Also, I can use GPU accelerated rendering in Blender.

Trying to find CUDA

This means CUDA has to be somewhere on my Ubuntu 18.04 system. Running the following commands returns various paths and information:

$ locate cuda | grep /cuda$
/home/user/Downloads/blender-2.83.3-linux64/2.83/scripts/addons/cycles/source/kernel/kernels/cuda
...
/home/user/anaconda3/lib/python3.7/site-packages/torch/cuda
...
/home/user/anaconda3/pkgs/pytorch-1.6.0-py3.7_cuda10.2.89_cudnn7.6.5_0/lib/python3.7/site-packages/torch/cuda
...

However, adding /lib64 to the command ( locate cuda | grep /cuda/lib64$ ) returns nothing.

Some more output:

$ nvidia-smi 
Sat Sep  5 18:01:44 2020       
+-----------------------------------------------------------------------------+
| NVIDIA-SMI 450.66       Driver Version: 450.66       CUDA Version: 11.0     |
|-------------------------------+----------------------+----------------------+
| GPU  Name        Persistence-M| Bus-Id        Disp.A | Volatile Uncorr. ECC |
| Fan  Temp  Perf  Pwr:Usage/Cap|         Memory-Usage | GPU-Util  Compute M. |
|                               |                      |               MIG M. |
|===============================+======================+======================|
|   0  GeForce GTX 108...  Off  | 00000000:26:00.0  On |                  N/A |
| 33%   43C    P0    67W / 260W |   1092MiB / 11176MiB |      5%      Default |
|                               |                      |                  N/A |
+-------------------------------+----------------------+----------------------+
                                                                               
+-----------------------------------------------------------------------------+
| Processes:                                                                  |
|  GPU   GI   CI        PID   Type   Process name                  GPU Memory |
|        ID   ID                                                   Usage      |
|=============================================================================|
|    0   N/A  N/A      9015      G   /usr/lib/xorg/Xorg                737MiB |
|    0   N/A  N/A      9145      G   /usr/bin/gnome-shell              343MiB |
|    0   N/A  N/A     11901      G   /usr/lib/firefox/firefox            2MiB |
|    0   N/A  N/A     11987      G   /usr/lib/firefox/firefox            5MiB |
+-----------------------------------------------------------------------------+

Installing CUDA Toolkit from the developer website - attempt

Also, after downloading CUDA Toolkit 10.2 runfile from the developer website, and executing the command: sudo sh cuda_10.2.89_440.33.01_linux.run,
I get the following warning:

Existing package manager installation of the driver found. It is strongly recommended that you remove this before continuing.

Question

To what folder do I have to set LD_LIBRARY_PATH? / How do I find the location of CUDA, or more specifically: cuda/lib64?