You can find the Weekly Timesheet by clicking on +New section, hdm-helpdesk.
After clicking on +New, you will find the Weekly Timesheet under the Team section. From there, you can enter the employees or vendors for whom you want to record the timesheet. Select the week for which you want to enter time and fill out the remaining fields before clicking Save.
I'll add this screenshot below for your visual reference:

On top of that, I'll add this article for reference in entering your timesheets: Enter a weekly timesheet.
I'm more than willing to help if you still need further guidance about the new QuickBooks Online update. We'll ensure your needs are taken care of, hdm-helpdesk.