In 2014, Lam led Diocesan Boys' School to the Hong Kong Inter-School Football Competition championship and was named season MVP.
His performances soon attracted the attention of scouts and he was offered opportunities to join the youth teams of Guangzhou Evergrande and Shandong Luneng.
[3] In March 2016, Lam and his Chelsea School teammate Tse Ka Wing travelled to England to seek out an opportunity to join the youth academy of an English side.
As a result, the pair could not receive work permits in order to play in the Football League Youth Alliance with the rest of the squad.
[12] During preseason training in Portugal, Lam injured his anterior cruciate ligament, necessitating a long layoff to recover.
Head coach Yeung Ching Kwong selected him ahead of the 2014 AFC U-16 Championship despite being a year younger than some of his teammates.
On 26 March 2024, Lam made his debut for the senior Hong Kong national team in a World Cup qualifier against Uzbekistan.