I want to directly start with list of options to the user before the first input from user. Like on clicking of the bot the bot should ask user What can I do for you? Please let me know how to go about it.
This is going to be possible depending which channel you are using.
The reason for that is that first of all you need to know that the user is there. If you plan on using an webchat widget. You could embed the question/buttons on the widget itself you wouldn’t even need to start the action on the bot and as the users responds to it. It would start as the first interaction on the bot.
Another approach would be to when you load the widget on the website you send a default message to the bot, without showing to the user, that would trigger the first action. (I usually find this approach a better option)