UTF - NewBie to Unified test Agents

[IbrahimUmar]

Hi Guys
I am using TFS2018 and already using Automated Builds. I have a Build definition and an agent where build gets compiled and copied to different Test Machines. Code get tested here and the results get published.
Our test cases are written as a project in main code solution which also compiled.
No one told how to set up or adjust UFT in already running Builds or convert older machines to newer UFT structure. Secondary, how to create/setup pool of machines as Test clients to cater to multiple project needs.
How can we deploy and test using the same agent if you wish to do so?

Step by Step Guide is also required which can help the people like me.

Looking forward to hearing from you.