Press CTRL+SHIFT+ALT+P
to open the Preferences window. Within this window, select the Console
item on the left, then the Advanced Settings
tab. The path to the Python executable will be right there.
Update:
For later versions please navigate to Tools -> Preferences -> Python Interpretor
Additionally, you might also need to follow an additional step to install the “spyder-kernels” library in python for which you have set the path using pip install spyder-kernels
before restarting Spyder.