The footage is from the 1982 animated version of Treasure Island produced by Kievnauchfilm .
Search for "Dr. Livesey Walk Full" or "Why Not Phonk Treasure Island." FlatScornfulDodo.mp4
The specific file FlatScornfulDodo.mp4 is often archived there as a high-bitrate version of the meme. The footage is from the 1982 animated version
The video file named is a well-known viral clip, most commonly recognized as a high-quality loop of the character Dr. Livesey from the 1982 Soviet animated film Treasure Island . FlatScornfulDodo.mp4
Because this file is a widely shared internet artifact, you can find the "full piece" (the complete walking loop with the Phonk music) on most major video platforms: