The 21-year-old became Kenny Dalglish’s first summer signing when he moved to Merseyside for £16 million from Sunderland.
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And the England Under-21 international, who has won one cap for the senior side against France, says he is ready to prove he was worth every penny.
"Liverpool are a massive club and I'm grateful to be part of it," he told the club's official website.
"It probably hasn't sunk in properly yet, but I'll keep working hard, keep doing the things I was doing at Sunderland and hopefully I can improve.
"There are big expectations and demands but that comes with football. You're going to get that wherever you go and it's about how you deal with it.
"I'm looking forward to the challenge. I'll just keep working as hard as I possibly can and hopefully I can put some good performances in for Liverpool."
Henderson is one of English football’s biggest prospects and, after a number of impressive displays for the Black Cats last season, won their Young Player of the Year award.
The midfielder is now looking forward to the new challenge of playing for Anfield legend Dalglish.
"Everyone knows what he is like, he is a brilliant manager and just as brilliant as a person," he said.
"He's been great with me and with everyone and he is someone that you look up to.
"The manager is one of the best managers around and he can help me with my own career and with the rest of the lads as well.
"I think that's great for everyone and I'm looking forward to working with him and everybody else."
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