I learned that I could create an application on shinyapps.io and publish it to the world.
I would like to make a web application published on shinyapps.io that scrapes the weather and temperature from weather forecast sites every day and make this available for download as a record and txt.
Does shinyapps.io just display a screen when it receives an access request?
Is it possible to scrape at a set time, generate a file, and make it available for download?
Shinyapps.io is a PaaS (Platform as a service) kind of service not a general Cloud Computing service so you don't get persistent data storage or background jobs. A container is launched when a user requests access to your app and discarded after a period of time without active sessions.
A general purpose virtual server would be more suitable for the application you are describing.