When i try to deploy the app in www.shinyapps.io from Rstudio it is throwing an error "Error in deployApp() : could not find function "deployApp" " Could anyone please help to deploy the app with any reference link. Thanks in advance
That error message suggests the
rsconnect package isn't installed and/or not loaded into your environment yet.
ginberg's suggestions are a great place to get started.
On specifically deploying your apps to shinyapps.io, check out the detailed guides at: Shiny - Share Deployment - Run your app on a server.