Create a web page for user journey flow

We want to create a sankey chart (flow) without using any [login to view URL] are the detailed requirements of the flow. HTML Canvas-5 or D3.js must be used. Our platform has been built using Angular-8 and Python. The data should be sent to backend in JSON format. This flow is represented in a diagram similar to a flow diagram. The flow will always have a root node with which the journey starts. On clicking the root node the flow will be shown, one level at a time. This level will be collapsible. For eg. From Root Node, a user clicks Book Car, Another user clicks rent a car, third one clicks Help,etc. Here, once client clicks on root node, 3 nodes will open, one having Book Car, Rent a car and Help. If you click on Root node again, the 3 nodes will hide again. All data will come via integrations. Each node on hover will show a dialog box having 3 things: % of user messages: Out of the total users what percent of users went to this particular node. Total no. of messages: Out of the total users how many users went to this particular node. Exit %: What percent of users dropped out from this node. Each node will by default show exit percent as well, without hovering over the node. The root node will also have these three parameters on hover. The % of user messages here will be 100%, total no. of messages will be the no. of interactions with the bot and the exit percent will be 0%. From the root node the bifurcations to different nodes will start as explained.