There is no one right thing to say at a funeral service. In some way, we’re all doing our best to express the jumble of feelings that surface with the loss of a father. One way of expressing those feelings is through poetry; and more specifically, funeral poems for dad.
The feelings you are experiencing can include heartache, sadness, regret, joy at his memory, humility and awe at his legacy, and perhaps some mixture of bitterness and respect, love and anger, longing and peace.