You need to clarify why your speech is bad. Is it some sort of impediment? language difficulties? lack of practice? Joining Toastmasters is a good option. They

You need to clarify why your speech is bad. Is it some sort of impediment? language difficulties? lack of practice? Joining Toastmasters is a good option. They focus on helping people improve in speaking in a variety of settings. Speaking well takes time, effort and practice. I doubt there are any easy shortcuts.