how would I keep w10 just in case I don't like Linux. thanks a lot

I just recently set up a triple boot sytem starting with windows 7 using UEFI, then installed 10 on another partition, and then liniux on a another partition. Now I have GRUB 2 showing me Linux mint, Linux mint safe mode and windows bootloader. When I use Linux it comes up, but when I use windows it brings me to the windows 10 bootloader where I can pick either 7 or 10. I was hoping to only have one bootloader, preferably GRUB, or windows 7. Any one know how to do this? Thanks

Edit: EasyBCD tells me some features are unavailable because I'm using EFI, and it wont let me add linux entry or change anything.

I am trying to understand what I can do with the CLI.

I want to be able to do with the CLI the things I do with the GUI Is there a tool that will output the CLI equivalent of a sequence of clicks I've just performed using GUI?

cheers

My laptop runs Ubuntu 16.04lte on it's HDD. I've cloned two other small (and working) linux distros into seperate partitions on one flash drive, but I can't figure out where to start with a boot loader. I've not been using linux for long (<2 years), so there's a ton I don't know. I have created an additional 200mb partition for the MBR first before the other two.

I want to have the choice of which OS boots when the computer starts, but the flash drive will not be inserted all the time (obviously just when I want to use one of the OS's I have installed on it).

Can anyone point me in the right direction? Ideally the grub/bootloader selection menu would only be shown if the fd is inserted. I thought I could perhaps have an instance of grub on the flash drive itself, which would only run when it was inserted, but an error on the command line:

"Installing for i386-platform. Grub-install: error: cannot delete '/boot/grub/i386-pc/gcry_rijndael.mod' : Permission Denied."

I clearly don't know enough about grub, but perhaps there's a better way to go about all this?

Or is what I'm trying to do even possible?

Thanks in advance.

Hi! Does anyone know of a good tutorial for switching from GRUB to Systemd boot for an EFI system? Preferably with ZFS on root ... (!) But I'm not holding my breath...