The Reds were rampant against Hoffenheim in their playoff second leg at Anfield, racing into a three-goal lead 21 minutes in and sealing a 4-2 win on the night.
The result sees Jurgen Klopp's side easily reach the group stage of Europe's elite competition, their opponent swept away 6-3 on aggregate.
Henderson told BT Sport: "It has been a brilliant night, the atmosphere was brilliant all night and we were brilliant at the start and set the tempo.
"We let in a couple of goals so we have still got things to work on but overall we're delighted to get back into the Champions League where Liverpool belong.
"Getting back in to the Champions League was our aim and we've done it. Now when we get into the Champions League itself we have got to do ourselves justice and win some games there.
"I'm delighted for the lads and the fans. We're in there and we've proved we can play against big teams. We're happy to play against whoever we're drawn against."
Liverpool have returned to the Champions League group stages for the first time since the 2014-15 campaign.