The 33-year-old joined from Liverpool on Friday, signing a two-year contract to become Tony Pulis’ third summer recruit after the arrivals of James Chester and James McClean.
He made his Baggies debut on Friday, scoring twice in a 4-0 victory over Bristol Rovers, and has set his sights on regaining his place in Roy Hodgson’s squad.
“It is only two years ago that I scored against Scotland,” Lambert told the Birmingham Mail.
“I scored 15 goals and then 13 goals for Southampton and obviously it is over a year since I did that but I have just got to get back to that now.”
Lambert made his England debut while at Southampton but fell out of favour after moving to Liverpool last summer, where he only managed seven league starts.
However, he refused to speak critically of his time at his boyhood club.
“I’ve got a lot of feelings, to be honest. I’m not going to get into it right now,” he added.
“I feel as if I’ve got a point to prove to myself. That’s always the biggest drive, yourself. And it will carry on being that way.”
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