There is a lot of information out there about this subject. I have read several articles about how important eye contact is when speaking in public I will share briefly three points about this.
1. Practice eye contact
Like anything in our lives it does not necessarily come natural to all of us and even cultural differences come into play here. As you interact with people make it a point to make eye contact with people. You can practice doing this in a mirror. If you have online video calls for work or something, practice eye contact by looking into the camera
2. Before being to speak during your presentation.
At the beginning of your speech before you even begin to speak take a pause and look at your audience. Look left and right and see all of them. This helps to ground yourself and connect with your audience before speaking.
3. During your speech make eye contact with one person for three to five seconds and then move on to another person. This time frame is typical amount of time it takes to finish a sentence or make a point.
Eye contact is an important part of speaking both in conversation and in public speaking. It is worthy of our attention and practice to make us better speakers.
There is a lot of material about eye contact and public speaking out there here are a few articles I references in writing this educational moment.
https://janicetomich.com/five-tips-making-eye-contact-public-speaking/
https://www.linkedin.com/advice/0/how-do-you-balance-eye-contact-gestures-when-speaking
https://www.quora.com/What-are-steps-I-can-take-to-improve-my-eye-contact-when-speaking-in-public
https://www.toastmasters.org/resources/public-speaking-tips/gestures-and-body-language