Milner will join the Merseyside outfit next month when his current contract with Premier League rivals Manchester City runs out.
The England international midfielder won two Premier League titles, an FA Cup and the League Cup during his five years at City.
Former Liverpool and Spain international attacker Garcia believes that Milner will prove to be a good signing for Liverpool.
Micah Richards is also set to leave City at the end of the month when his contract with the former Premier League champions runs out.
The England international defender has wished Milner the best of luck at Liverpool on Twitter.
Milner has been on the books of City since 2010, but he has never really been guaranteed a regular place in the starting line-up.
The former Leeds United and Aston Villa star scored five goals and created 52 chances in 32 Premier League appearances in the recently concluded 2014-15 campaign, while having a pass accuracy of 79% and a shot accuracy of 41%.
The Englishman is not one of the most technically gifted footballers, but he is an all-round midfield player who works hard and does what he is told.
Given that Milner has loads of Premier League experience and is not going to cost any transfer fee, it could prove to be a good piece of business for Liverpool.