ST. ANDREWS, Scotland — Cameron Young wasn’t yet a teenager when he first stood on the first tee of the Old Course at St. Andrews.

He needed permission from the powers that be at the Royal & Ancient club to play what they call the “medal’’ tees so he could play the course at its longest length. Tourists are not permitted to play the medal tees unless in an official competition.

Young’s father, David, the longtime golf pro at Sleepy Hollow Country Club in Westchester County, asked for permission and it was granted.

For the opening round of the 150th British Open on Thursday at the Old Course at St. Andrews, the younger Young, now a 25-year-old PGA Tour rookie from Scarborough, needed no permission. He was, in fact, about to take the first-round lead in the British Open.

Young shot a blemish-free 8-under 64 while playing in his first career British Open. He leads Rory McIlroy by two shots, Cam Smith and Robert Dinwiddie by three and several other players — including world No. 1 Scottie Scheffler, Lee Westwood and Viktor Hovland — by four.

Sure, it was only one round, with three still to play. But what a ride 2022 has been for Young, who was ranked 1,188th not even two years ago.

Young, now ranked No. 32, has posted three runner-up finishes and two third-place results this season — one of which was at the PGA Championship at Southern Hills, where he had a piece of the lead on the 15th tee in the final round.

That experience was immeasurable for Young.

“I think any time you’re around the lead in a major championship or any PGA Tour event, frankly, you get more and more comfortable every time,’’ Young said. “I feel like — even though it’s only been most of the year — I’ve been around the lead a good bit, and I think we’ll just take [Friday] as it comes. That’s really all I can control.’’

One thing Young controlled recently was what had to be a difficult decision to change his caddie. He had Scott McKean, his longtime Wake Forest college pal and best man at Young’s wedding, on the bag for the balance of his pro career. But Young recently went with Chad Reynolds, a more experienced PGA Tour looper who has worked for Vijay Singh, Nick Watney and Keegan Bradley.

“As much as I’ve had a solid year, there’s been a couple things missing, I think,’’ Young said, explaining his reasons for the change. “I haven’t won anything, and that was just something that could change to kind of exhaust all my options to see what I could do better. That was just something that we as a team decided was probably best for my golf.

“There’s no replacement for being around good golf and major championship golf for 20 years. There’s just a level of knowledge that is hard to find elsewhere. That knowledge is kind of irreplaceable.’’

So, too, are the experiences such as the one Young took to Scotland with his parents, David and Barbara, in 2008.

“I think we played eight or nine golf courses in six days — here at the New [Course], the Old [Course], we played Kingsbarns, Carnoustie, Gullane,’’ he said. “When we came out to hit our first tee shots with the R&A building right there, there were a bunch of R&A members presumably watching. I’m glad I didn’t know. I’m sure I would have been nervous out of my mind. I think there’s a picture of me hitting there with a bunch of those guys watching. That’s really my first memory of here.’’

On Thursday the R&A members were watching the eventual first-round leader, and possibly their next Open champion.

“Any time you set foot on the first tee or 18th green or anywhere … there’s just no hiding how special of a place it is,’’ Young said. “It’s certainly been a goal to get to an Open Championship. And for my first one to be here is a little bit extra special for me.’’

Young, who graduated from Fordham Prep before he went to Wake Forest, was asked by a British reporter about The Bronx not being especially known for producing professional golfers. He was asked about his “improbable journey from the streets of New York to the links of St. Andrews.’’

“I think the streets of New York is probably a stretch,’’ Young said with a smile. “Fordham Prep is on the Fordham University campus. It’s beautiful. And I lived at Sleepy Hollow Country Club, where my dad is the head pro. I took the train to school, but I also took the train back home to go practice. It might sound a little improbable, but I’ve been around golf my whole life. That’s just kind of what I do.’’