Please check the following for the difference between Enhanced BOT and Standard BOT in Salesforce.
Enhanced BOT
Enhanced BOTs use Omni-Channel Flow for routing to agents, bots, queues, and skills, and connections for routing to Slack and the Einstein Bots API.
Enhanced BOTs allow us to use Rich content such as files and hyperlinks in the BOT conversations using the Messaging Components.
To take advantage of Salesforce AI features, we have to add Enhanced BOT to our Messaging for In-App and Web channels or enhanced Messaging channels.
Standard BOT
Standard BOTs cannot use Omni-Channel Flow for routing.
Standard BOTs doesn’t allow us to use Rich content like files and hyperlinks in the BOT conversations using the Messaging Components.
Standard Salesforce Messaging channels support standard BOTs.