Time Machine backs up everything, data, apps, system preferences, Mac OS.....EVERYTHING!
To restore your old data to a new Mac please do one of the following:
- If you have not turned on the new Mac for the first time, connect the Time Machine backup External Hard Disk using a USB cable to the new computer. Start it and it will launch Setup Assistant (SA), SA will get to a point where it asks if you are migrating from another Mac, select YES and follow the on-screen prompts.
- If you have already turned on the new Mac, connect the old Mac's Time Machine backup External Hard Disk using a USB cable to the new computer and launch Migration Assistant (MA). Follow the on-screen prompts.
Either SA or MA will migrate everything, however it will not migrate the old version of Mac OS over the new machines version of Mac OS. You can tell it to migrate only apps and/or settings and/or data files.
Your new Mac will likely come with Mac OS Catalina, Catalina will ONLY run 64 bit applications. So if you have some 32 bit apps installed on the old Mac they will NOT run on Catalina. Using System Information - Software - Applications get a list of the 32 bit apps on the old computer and either upgrade or replace them to 64 bit version prior to migrating. If you don't care about an old 32 bit app you can leave it alone.
NOTE: Some professional apps from developers such as Adobe & Microsoft will NOT migrate. The data files will, just not the apps so you have to manually re-install them.