How to learn english idioms from a book, is it efficient?

26 american but hispanic male. born in usa. but since i never opened my mouth from age 6 to 26( kinda) and never had friends who spoke engglish( nor had friends who spoke spanish) my languages are lacking in skill.. i decided i want to learn all that which normal americans know and i bought a book entitled "AMERICAN IDIOMS". if i just go one by one and try to memorize them and understand them, will i be better at speaking? even if i dont' practice with noone? or is it useless? usually there is no way for me to make American friends, unless they want to learn spanish.. they would put up an ad in the paper but i'm not even good at spaniish so there goes that one.