Complete first section of windmill, house and hotel inside Lego set (5-3)

'complete first section' is the definition.
The definition suggests a singular noun which matches the answer.

'windmill house and hotel inside lego set' is the wordplay.
I cannot quite understand how this works, but
'house' could be 'ho' (abbreviation for house) and 'ho' is found within the answer.
'hotel' could be 'h' (phonetic alphabet: alpha, bravo, charlie etc.) and 'h' is present in the answer.
an anagram of 'lego' is 'leog' which is located in the remaining letters.
A single letter 'w' remains which might be clued in a way I don't see.
This explanation may well be incorrect...

'of' acts as a link.

Can you help me to learn more?