Cardiff Blues flanker Botham, 22, made his Test debut in the 18-0 win over Georgia last weekend and he will win his second cap against England.
“It’s a massive step up,” said Botham.
“Only last week I was called in for the Georgia game and now obviously it’s the biggest game I have ever come up against. It will be interesting to see how we go.
“I have just kept my head down and got on with it. That’s all I can do – try and perform the best I can and do everyone proud really.
“The Georgia game was a big step up from playing for the Blues. I kind of suit the faster game and going forward, I can’t wait. It’s going to be even more of a bigger step up this weekend.
“It’s just dealing with that and getting on with it.”
On the challenge this Saturday, Botham said: “I can’t wait. It’s a dream come true. I have literally dreamed of this moment since I was a kid chucking a ball around.
“Hopefully I will do everyone proud. Words can’t really describe it. This is probably the one thing I have worked for my whole life – to get the jersey and play against England.
“Obviously everyone gives me stick about the family being English and stuff, but in my heart it’s Wales through and through and the family know that.”
On playing at openside, Botham continued: “I prefer to play seven. Playing with Shane at six will be great.
“I just want to bring some physicality over the ball and with the ball so it will be good to play with him again.
“I can’t wait to get out there and play with one of the brothers.”
