Can I use examples of others' research in my presentation on scientific conference? I'm giving a talk on scientific conference in a couple of days and I have prepared my concept and my presentation. Because what I'm going to talk about is not done in practise in my country, I have included in my presentation examples and research results from the past from other academics and researchers.

Is this okay? I will also give credits underneath each slide to the respected researchers.
Yes, it's fine to do that. If you do an introduction on the topic or you are comparing your results/methods to others you can talk about/show their work and you even should do that.

Just be careful that you talk enough about your own research and you always make it very clear if something was done by someone else.