If you are looking to any king of modification on your Samsung Galaxy Note 10 + (plus) variant, you will have to install the TWRP which is a kind of custom recovery. This TWRP will allow you to install all sorts of mods and custom firmwares / ROMs on your device.
There are two TWRP for the Samsung Galaxy Note 10 + (plus) variant – one is for the Exynos (N970/971/975/976/N/F/B) and another is for the Snapdragon variant which includes N9750, N9700.
First download the TWRP according to the chipset you have on your Note 10 Plus
* Go to Developer settings and enable oem unlock
* power off the device and boot in download mode with power + vol down buttons and plug in the usb (make sure usb cable is connected to the pc)
* in download mode you see the long press vol up option for unlock bl
* unlock the bootloader (that will wipe your device so be sure you made a backup of your data)
* after bootloader unlock boot up the phone and make sure it is connected to the internet or he triggers rmm prenormal
* setup the phone without google account etc
* reboot in download mode and flash the magisk prepatched tar for your device with odin in the AP field (if you want to patch * twrp byself download unpatched tar and select it in magisk manager. patched tar is in downloads folder after patch)
* hold vol up + power button while odin is flashing until you are in twrp.
* format data in twrp
* flash the multidisabler zip by ian in twrp
* press reboot to recovery in twrp for boot rooted with magisk.