adding web hooks url but it’s not giving the information on slack?
No it does not. The webhooks sent by SonarCloud are in a specific JSON format that is not supported by Slack. You should implement your own bridge that redirects SonarCloud webhooks to Slack.
Talking about Slack, which kinds of notifications would you like to receive? All the ones already supported in My Account > Notifications? Other ones? What about the status of analysis on pull requests, …?