In the management console, in Reporting/Reports. Note a range like Today is "today up until now" so it can be run at 11:59 pm for a full day, or use Yesterday.
Note also 3CX does not automatically prune old reports.
Ah, you posted in Hosted not StartUP. StartUP Pro has Call Reports: https://www.3cx.com/ordering/pricing/. There is no upgrade path from either StartUP version to Pro or Enterprise.