I have the installed the bash of the Linux sub system on my Windows 10 now for quite some time.

Today the prompt informed me about available updates for packages. I tried to sudo to run the apt command but failed.

{account} is not in the sudoers file.  This incident will be reported.

So I had a look at the /etc/sudoers file:

...
# Members of the admin group may gain root privileges
%admin ALL=(ALL) ALL
...

So I decided to not modify the file and add my account to the admin group:

usermod -aG admin lennybacon

Now I can sudo!

HTH,
Daniel