You can try to get your GRUB back instead of going with third party tools like EasyBCD.
First Disable Fast startup on your windows. To do so :
On your windows 10,
open command prompt as administrator and execute powercfg /h off
Now, Go to Control panel --> Power Options --> Choose what power buttons do (its on Left side) --> "Change Settings that are currently unavailable"
and remove the tick mark on "Fast startup"
This disables fast start up on windows (Which is mandatory on dualboot).
you should see your Grub. nice and clean.
If you have already tried EasyBCD you may have messed up your boot loaders. If so do this:
Go to your Multi-boot manager during startup ( On HP notebooks Keep pressing f9 as soon as you power on your machine, f12 on Dell notebooks ) and manually boot to Ubuntu.
Restart after doing the above steps. Go to your BIOS.
Go to boot section and Under Boot loaders (Or similar) and bring the "Ubuntu on HDxxxx" option above Windows boot manager.
Now reinstall grub by running the following commands :
sudo grub-install /dev/sda
#link - https://askubuntu.com/questions/787744/windows-10-and-ubuntu-16-04-lts-dual-boot-problem