i don't have migration assistant in my mac
just have a new MacBook air, and want to migrate from old MacBook Air to the new one. But I didn't find migration assistant in my Mac.
MacBook Air 11″, macOS 10.15
Open a Finder window; use the Finder "Go" menu and click Applications on that menu; scroll down in the Applications folder and open the Utilities folder and you should see Migration Assistant;
or an easier method -- click the magnifying glass Search icon near the right of the menu bar and search for it.