We need some template or forms for Sharepoint pages and I want to ask Is it possible to do in Sharepoint Online:
Page with form "Holiday request". Employees fulfil this request with some date range - from when to when they will be absent. After submitting a request it is being sent to the right person who can approve or decline. When this person approves it, the correct date range will appear in a group calendar.
Unfortunately, most of the tutorials and guides refer to the previous versions of Sharepoint, not to Sharepoint Online with modern sites.