Auch im Winter trinken wir abends Tee im Wohnzimmer.

to drink

Breakdown of Auch im Winter trinken wir abends Tee im Wohnzimmer.

• wir: we
• das Wohnzimmer: the living room
• im: in the; (masculine or neuter)

Questions & Answers about Auch im Winter trinken wir abends Tee im Wohnzimmer.

Why does the sentence start with Auch im Winter? What is auch doing here?

Auch means also / too / even. Placing it at the beginning gives it emphasis and links to something previously said (e.g., “We drink tea in the evenings. We also do so in winter.”).
So Auch im Winter ... ≈ “Even in winter ... / In winter as well ...”
You could also place auch elsewhere depending on what you want it to modify, but here it clearly highlights im Winter.

Why is the word order Auch im Winter trinken wir ... and not ... wir trinken ...?

German follows the verb-second (V2) rule in main clauses: the finite verb (here trinken) must be in position 2.
If you put something other than the subject first (Auch im Winter), then the subject moves after the verb:

• Auch im Winter (position 1)
• trinken (position 2)
• wir (after the verb)

This is normal and doesn’t sound “inverted” the way it might in English.

Does Auch im Winter count as one unit in the word order?

Yes. Auch im Winter functions as a single fronted adverbial phrase (a time phrase). Even though it contains two words, it occupies the first “slot” of the sentence before the verb.