The world number 301 became the youngest player to qualify for the main Wimbledon draw since the Open era began in 1968.
She says the Williams sisters were her idols growing up and that Serena is “the reason why I play tennis”.
“I kind of felt like I was going to play one of them,” Gauff said.
“Many people have been like ‘do you like your draw?’ – I love my draw. Playing one of the greatest players of all time is a dream – I’m excited to see how I do.”
Gauff, who will be the first 15-year-old in the main draw since Britain’s Laura Robson in 2009, received a wildcard to get into qualifying.
“I found out last minute,” she said. “I wasn’t even packed to come here so it’s just crazy how life can turn around in a second.”
In facing Venus, she takes on a player 24 years her senior who has won seven Grand Slam singles titles, five at the All England Club.
Of the age gap, Gauff said: “I don’t think of Venus as old – she’s still killing the game right now.
“It’s crazy to show her longevity – that’s how I look at it. I hope I’m still playing and doing well at 39.”
‘She reminds me of Venus’
It is Venus’ younger sister Serena who features in a poster on Gauff’s bedroom wall in Florida – “a reminder to work hard every day”, according to the youngster.
And the 37-year-old, winner of 23 Grand Slams, is a fan.
“She’s an exciting young player, and she’s so cool,” she said. “She’s a great girl, I love her dad – they’re just really cool people
“It’s a great moment for her and for Venus.
“It’s going to be a big moment for Venus as well – she’s playing against a player who reminds me of Venus. Just her body and everything.”
Gauff reached the US Open girls’ final aged 13 in 2017, and won the French Open girls’ singles title a year later.
Asked about being called “the future of tennis”, she added: “It’s crazy that people call me the next this, next that. I’m just trying to be me.”