Yes. There are several ways to open the built in Bush Trips, but the easiest way is to at least start the first leg of the bush trip in-game. If you don’t want to fly the whole leg, just taxi down the runway a few feet, then exit to the Main Menu. Flight Simulator will create a save file of the Bush Trip in your MISSIONS\ACTIVITIES folder (in your Flight Simulator install folder). You can open this file in Flightplan and view the current leg or the entire Bush Trip. To fly any leg(s) of the Bush Trip, just save it to a new Flightplan and open it through the World Map in Flight Simulator.
You can also open the entire Bush Trip in the Official\OneStore folder (in your Flight Simulator install folder) by finding the Bush Trip in the list folders that contain all MSFS content. Typically Bush Trips are prefixed either asobo-bushtrip or microsoft-bushtrip. If you don't know where your install folder is, use Windows Explorer to search your hard drive for either term ("asobo-bushtrip" or "microsoft-bushtrip"). It should find the location for you. Within these folders are the "template" Bush Trip flight plans that will contain all legs of the Bush Trip. These should not be modified, but you can save the file to a new location and modify it in Flightplan.
Understand that by opening and saving the Bush Trip in Flightplan it will be converted to a "Free Flight" type flight plan. This means that you will not get credit for flying the leg on the Bush Trip in Microsoft Flight Simulator - the percentage complete will not change. But you can use this technique to practice challenging landings, or "cherry picking" the Bush Trip to just fly the most scenic legs. You can also change the aircraft to something easier to fly or with better visibility.
Check out the How To videos on our YouTube channel for more information https://youtube.com/@simflightplan