My LO is 13 months old n is still crawling and cruising .. I'm worried why he hasn't started to attempt to try to walk.

Let baby go at own pace. U can also put things around baby that may allow him to explore to stand and also to walk. Like the mat is beside the wall or there is a steady big box that he can hold and push himself up etc. but u have to be there for some of these aids. Let baby decide when he wants to walk