Talk to Pediatrician on Speech Problem

Aoa I have a question regarding my son he is one yr and eight months old but he did not speak . initial mama baba kehta rha but ab bs shout krk bat smjha deta ya hand k isharey se .wese bat ko smjhta hy koi kam kahen tu understand krta like door band krdeyga remote dyga agr mangen tu.kia ye sab normal hy ya abi chota hy Kuch b bolny k liye.kindly guide kren.