Roscoe, the contents of the SD Card will NOT be included in the backup. This basically contains:
- the list of installed apps. When you restore, these will also be reinstalled fresh from store in the current version in store
- most but not all settings. E.g. native vpn connection settings are not included for some weird reason. also Bluetooth targets like your car are not there
- app data of many apps - for me, most work right away after restoring after a hard reset. Unfortunately it is still hit and miss, as the developers must support it. You can try to check what apps do have any app data included in settings - update and security - backup - additional options. If an app is not listed there, it will not have app data (app settings, game levels, whatever) restored. If it is there, it may or may not have it restored. Many apps are great here (Nextgen reader, twitter, life360, Microsoft RDP...) are coming out of this perfectly great. Others need to be setup fresh (Teamviewer (not listed), Skype for business (listed and lots of data, but no use) .
IF you configured auto upload of photos and videos created on the phone to onedrive in the onedrive app, these will be backed up there. But this has nothing to do with the native backup in settings.
Regarding SD Card contents: You should move apps away and copy media contents to the MAC and then format the card in the phone:
- do not install apps to SD card, if possible. I, personally, prefer a lot having them on the device
- if apps are on the SD card, copy them to the phone via settings -> system -> storage
- shut down the phone, take out the SD-Card
- put it into a micro sd card reader (they can be had for some €$GBP), put it into your mac and copy the contents over
- put it into the phone, power it up and format the SD Card IN THE PHONE (settings - system - storage - tap sd card - scroll down - format)
- power down, take it out, put it into the mac, copy back contents, back into the phone. Done. Phew.
I am not sure, what a MAC will show when you connect the phone via USB. A windows PC shows you the SD Card and you can copy media contents off. Using the method with the external reader has the advantage, that e.g. map data also gets copied off the card.