In the sentence "Anyi ga-alu oru echi," the question asks which word indicates time (oge). In Igbo grammar, an adverb of time (okwu na-egosi oge) tells us when an action takes place.
The word Echi means "tomorrow" and is the time indicator in this sentence. It tells us when the action of working (ilu oru) will happen - specifically, tomorrow. This makes it the adverb of time.
The other words serve different grammatical functions: "Anyi" (we) is the subject/pronoun, "ga-alu" (will do/work) is the verb phrase showing future action, and "oru" (work) is the object/noun. While "ga-" marks the future tense within the verb, it is a grammatical particle attached to the verb, not a standalone time word. The standalone adverb of time is "echi."