In the UK, 'license' is the correct spelling of the verb, whereas 'licence' is a noun.
e.g. "I will approach the licensing (verb) authority to seek a licence (noun). I will ask them to license (verb) the premises, which will then be licensed (verb)".
The convention is followed with other words, such as 'practice' and 'practise'.
e.g. "I am practising (verb) the piano because I need the practice (noun)".
However, that example could end with a different spelling by changing just one word. i.e. "I am practising the piano because I need to practise (verb)".
In the USA, 'license' is used both as a verb and a noun.
Perversely, Americans use 'practice', rather than 'practise', as both a verb and a noun.
Chris