Most adults in Commonwealth countries have heard this tune, possibly through military bands which still play it. It dates back to 1914, but the words came later during World War 2. It became famous worldwide with the film “Bridge on the River Kwai” which was released in 1957, but was still making the rounds of cinemas in India in the 1970s.
Here is the “official version” by a British army band: https://www.youtube.com/watch?v=yxguy0BYNzE
You are more likely to have seen this version from the film: https://www.youtube.com/watch?v=4k4NEAIk3PU
Although most of the film was shot in Sri Lanka, the actual bridge still stands in Thailand and is a popular tourist destination: https://www.youtube.com/watch?v=0nYT79oxzBI
It is not very close to Bangkok, but many conducted tours will take you there and back in a day.
The tune became so ingrained in popular culture that: “Since the film portrayed prisoners of war held under inhumane conditions by the Japanese, there was a diplomatic row in May 1980, when a military band played “Colonel Bogey” during a visit to Canada by Japanese prime minister Masayoshi Ōhira”
As to the lyrics, Wikipedia goes into them in great detail: https://en.wikipedia.org/wiki/Hitler_Has_Only_Got_One_Ball Most versions had only the first four lines, though longer versions exist. Variations in the second line mention local prominent buildings such as the Albert Hall in London and the Free Trade Hall in Manchester. Also, as General Rommel was one of the few German military leaders who was respected by soldiers on the other side, the second line sometimes became “Rommel has three but small”. The more obscure variations (particularly on the second verse) are here:
Indian schoolboys made up other variations such as:
Hitler, he had but one big ball,
Rommel, he had three but small,
Nehru, he went to Peru,
And poor Gandhi, he had none at all.