How to go back to Mission Control

Mission control is still there. If no key on keyboard then short cut is ctrl up arrow. Can also add icon in menu bar. Now if you mean the old Launchpad then you cannot get that back. See this discussion:

How do I restore the old Launchpad in mac… - Apple Community

KODIAKGRIZZLY-BEAR_01 wrote:

I have Tahoe now 26.1 (25B78 how to go back to mission control?

ref: View open windows and spaces in Mission Control on Mac

Could you be referring to Launchpad?

Launchpad was replaced by Apps and can't be changed. There is third-party software that can do the same thing such as Launchie.

You're welcome.