If you are using python provided by Anaconda distribution, you are almost ready to go.
Add conda-forge to the list of channels you can install packages from
conda config --add channels conda-forge
and install packages
conda install orange3
conda install -c defaults pyqt=5 qt
Now create the conda environment named orange3
conda create python=3 orange3 --name orange3
Activate the environment, run orange3 and finally deactivate it
conda activate orange3
python3 -m Orange.canvas
Moreover, you probably have Anaconda Navigator (the graphical interface to conda) in anaconda3 . Why not using it ?
Now the graphical interface to conda starts, then choose the orange3 environment, and run orange3