Try Power Apps and customer engagement apps apps
You can explore all Power Apps and model-driven apps capabilities in Dynamics 365, such as Dynamics 365 Sales and Customer Service, for free by signing up for trial licenses.
Power Apps trial
You can try Power Apps for free by signing up either for a 30 day trial or developer plan.
Customer engagement apps trial
Visit https://trials.dynamics.com and select the required app to sign up for a 30-day trial.
For detailed information about signing up, purchasing or using individual customer engagement apps, see the respective app's documentation at Dynamics 365 documentation.