Does word "one" have the same meaning in the following two sentences?

He has the one but will need a two and three to go with it.

They had lunch at one.

OPTIONS:
- different meanings
- the same meaning
the same meaning
Har ordet "en" samma betydelse i följande två meningar? Han har en, men behöver en tvåa och en trea. De åt lunch klockan ett. Alternativ: - olika betydelser - samma betydelse
Does the word "one" have the same meaning in the following two sentences? He's got one, but he needs a two and a three. They had lunch at one o'clock. Option: - different meanings - same meaning
samma betydelse
the same meaning