Switch into “presentation mode”
It is important to remember that to present well you need to be in “presentation mode” to have an impact. For example, if you are in a meeting and you are all sitting around a table, or sitting on a video call you are in “meeting mode” to have more of an impact in your meeting you should switch into “presentation mode”.
When speaking sit up (or even stand up) and adjust your body language/posture and tone, use your hands for emphasis etc. Your words will have much more of an impact if you present them (not just say them).