Thanks for reaching back out to the Community and letting us know you're not able to find this particular step. Allow me to give you some additional insight into integrating your QuickBooks Core Payroll and QuickBooks Time.
Any account can integrate with QB Time. I can see how beneficial this would be for you and your business. However, it's not included with your Core Payroll account. You can send feedback to our Product Developers so they can consider this to be available in the next update.
Although this is the case, you can start a trial to see what the QB Time has to offer before you pay the difference to integrate with your Core payroll account. Here's a link that can help you out: Integrate QuickBooks Time and QuickBooks Online . If you want it included with your payroll, you'll need to upgrade the account to Premium or Elite.
If you have any other integration questions, please let me know by adding a comment below. I'm more than happy to help. Have a good one!