As presenter in front of a group you have a lot of power to direct the presentation the way you like it. When you want to have an engaging discussion there are various things that you can do. There is an option that you will give one or more members of your audience an early warning that you are going to ask them a question to say or do something during your presentation. If you do that before your presentation you will allow them to think about it and prepare. By means of this you are sure that you will get a response during your presentation. The risk is that it will sound rehearsed, but this also depends on the individual person and how much time you will ask the person(s) before your actual presentation.
Another option is to say that you are going to volunteer someone of your audience to for example provide her/his perspective or comment on something. You can then point to someone or mention their name. Alternatively if you are using a microphone you can directly give the microphone to somebody if you don’t get any volunteers. When you say that “I am going to volunteer someone to react to xyz”, you bring it in a fun manner.