Sy-Alvarado earned a degree of Business Management major in Entrepreneurship at San Beda College.

Sy-Alvarado, then chairman of the House Committee on Good Government and Public Accountability, is one of the 70 representatives who voted to deny the ABS-CBN franchise on July 10, 2020.

[2] Due to the changes under new House Speaker Lord Allan Velasco, he was removed as the Good Government panel chair.

[3] In January 2021, he was announced to be part of the new bloc "BTS sa Kongreso" (named after the K-pop boy band group BTS of South Korea), a coalition group formed by Taguig–Pateros Representative and former House Speaker Alan Peter Cayetano during the 18th Congress.

He has 6 more siblings including Maria Rosario S. Mendoza, who currently serves as the vice mayor of Hagonoy, Bulacan.