I just installed an app now I wanna add this to the left sidebar. But I couldn’t figure out this. Please someone help me to resolve this.
Every module in ERPNext has its own Standard Workspace which is generated with appropriate shortcuts and links. Any customization to be made to the Standard Workspace can be done with Customize Workspace option in the top right corner of the Workspace.
that for creating the workspace in custom app/ custom module and check it.
more details for check it documentation