Rearranged by PSG Bandleader Major Xavier Celestial in 2012 and originally composed by famed prewar bandleader Tirso Cruz Sr. “Mabuhay” has been the presidential anthem since the administration of president Manuel L. Quezon.
In short, this song is the Philippine version of "Hail to the Chief".
The full lyrics have been published here. But all available recordings sing only the chorus and not the full song:
It may have been available at the Malacañang Palace Presidential Museum and Library page linked above, but the Soundcloud embed says "Oops, we couldn't find that track". The rondalla version also embedded on that page is available at the Internet Archive.