Install TWRP and root galaxy S10 Exynos [root]

Download  Termux terminal emulator



TWRP image file 



Place the multi-disabler.zip on sdcard 

Open magisk manager - install - select and patch an image , select the TWRP image

Reboot [don't forget to reboot to magisk with button combo - bixby, power & vol up]

Open Termux and enter this: 

Su 

f=/storage/emulated/0/Download/magisk_patched.img; dd if=$f of=/dev/block/sda15 bs=$(stat -c%s $f)

Reboot to TWRP

power, bixby, vol up , let go of power and keep holding bixby and volume up

In TWRP flash the multi-disabler zip - format data type YES

Reboot into magisk.

Note: it may take several reboots for magisk to execute the root.