Please refer below documentation which explains how to define a set of core commands that your bot can respond to. You can add a command menu with a dropdown list of commands for your bot
Ref: https://learn.microsoft.com/en-us/microsoftteams/platform/bots/how-to/create-a-bot-commands-menu?tabs=desktop%2Cdotnet
Sample code: https://github.com/OfficeDev/Microsoft-Teams-Samples/tree/main/samples/bot-conversation
The screenshot you have provided is of Suggested actions that will enable your bot to present buttons.
Ref: https://learn.microsoft.com/en-us/azure/bot-service/bot-builder-howto-add-suggested-actions?view=azure-bot-service-4.0&tabs=csharp&preserve-view=true#suggest-action-using-button
Sample code: https://github.com/OfficeDev/Microsoft-Teams-Samples/tree/main/samples/bot-suggested-actions