Undertakes to go east to the Ganges, possibly (7)

I believe the answer is:

engages

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'undertakes to go' is the definition.
I can't judge whether this definition defines the answer.

'east to the ganges possibly' is the wordplay.
'east' becomes 'e' (synonyms).
'to' says to put letters next to each other.
'possibly' indicates anagramming the letters.
'ganges' is an anagram of 'ngages'.
'e'+'ngages'='ENGAGES'

Can you help me to learn more?

(Other definitions for engages that I've seen before include "Employs, hires" , "books" .)

I've seen this clue in the Evening Standard.

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