The short answer is, “No.”
The long answer is, “It depends what you mean by ‘need.'”
God does not need us ontologically, that is in order to be himself. This is actually a key component of how we conceived of God as Trinity. God, by definition, is perfect. But it is impossible for a unitarian God to have relationship until that God creates something – the creature can then be seen to add/complete/perfect that God in some way. But if God is Father who eternally and perfectly pours himself out in perfect love into a perfect and complementary reflection of himself you have the basis of the “God in three persons” which in some sense is to understand “God as relationship.” A Trinitarian God does not need his creatures in order to perfectly incorporate relationship. His creation of us is therefore an act of grace, a gift, not an act of necessity or self-exploration on his part.
God does not need us practically, that is in order to do what he wants to do. This is pretty clear. God, being God, can do whatever he likes. He can create the heavens and the earth and doesn’t need our help. He can reveal himself to patriarchs and prophets, and doesn’t need our help. He can move mountains and quicken and harden hearts, and doesn’t need our help. All these actions speak of a God who graciously choose to create, sustain, and even intervene in his creation. This is a grace, a gift to us, and not an act of obligation on his part.
There’s a pattern here – it’s not about “need”, it’s about grace.
And one of the aspects of that grace is that God chooses to no only relate to us, but to lead us, guide us, and, yes, to work through us. So much so that he binds himself to us which not only affirms his humility, but also affirms that we are indeed made in the image of God, through whom divine works can occur. And so God achieves his project through a human. He even achieves salvation through a human. That perfect and creative outpouring of God the Father – i.e. God the Son – became, is and will ever more be a human being. He is a human being through whom God has worked his most magnificent work, and through whom we are called to also be, like Jesus, obedient to God, empowered by his Spirit, and achieving the works of his kingdom.
Are we needed for that task? In some sense, yes, but not out of necessity, only because God is both gracious and sovereign.