If you don't have an account, you will need a subscription to ArcGIS Online or ArcGIS Enterprise.
Before creating a web application, you should create the maps, layers, and other assets you need.
Use the most suitable app builder to create your web application.
ArcGIS Instant Apps
Create focused, purpose-driven web apps using ArcGIS Instant Apps.
Create dashboards to show location-based analytics on a single screen using ArcGIS Dashboards.
Create compelling digital stories using ArcGIS StoryMaps.
ArcGIS Experience Builder
Create mobile-optimized web apps using ArcGIS Experience Builder.