Wir drucken Bilder im Büro.

drucken is the verb “to print.”
Druck is a noun meaning “print” or “pressure,” and Drucker is a noun meaning “printer” (the machine). Since the sentence describes the action of printing, you need the verb drucken.

Bilder is in the accusative plural. In German, the direct object of a transitive verb takes the accusative case.
Singular: das Bild → Akk. das Bild
Plural: die Bilder → Akk. die Bilder

im is simply the contraction of in + dem.
Because Büro is a neuter noun (das Büro) and the preposition in requires the dative when indicating location, you use dem Büro, which contracts to im Büro.

German main clauses typically follow the pattern: Subject – Verb – (Other Elements). Adverbial phrases of place (like im Büro) commonly come after the direct object but can be moved for emphasis. The neutral order here is:
Wir (S) – drucken (V) – Bilder (O) – im Büro (Adv).

drucken: [ˈdʁʊkən] – the u is like “oo” in English “book.”
Büro: [byˈʁoː] – the ü is pronounced like the French “u” in “tu,” and the stress is on the second syllable.

Yes. You would use sie for “them” (accusative plural):
Wir drucken sie im Büro.
Context clarifies whether sie refers to “them” (Bilder) or “her” (sie = she).