boot - How to install Ubuntu on separate Windows partition?

I have two separate hard drives: C:\ with Windows 10 and D:\ with data. Now I want to make two partitions on D drive. One with 80GB for Ubuntu installation and other one with all data I have right now. I don't want to have dual boot screen at startup instead I want to optionally choose from which drive to boot. (By optional I mean pressing something like F10 button to choose drive without using grub.)

How can I perform such installation? Should I partition D drive in Windows and later install Ubuntu on that partition?

Most importantly I don't want to loose my data on D drive.

Output from sudo parted -l

Model: ATA HGST HTS541010A9 (scsi)
Disk /dev/sda: 1000GB


Sector size (logical/physical): 512B/4096B
Partition Table: msdos
Disk Flags: 

Number  Start   End     Size    Type     File system  Flags
 1      1049kB  106MB   105MB   primary  ntfs         boot
 2      106MB   1000GB  1000GB  primary  ntfs


Model: ATA PLEXTOR PX-128M5 (scsi)

Disk /dev/sdb: 128GB
Sector size (logical/physical): 512B/512B
Partition Table: msdos
Disk Flags: 

Number  Start   End    Size   Type     File system  Flags
 1      1049kB  128GB  128GB  primary  ntfs

sdb is my C drive and sda is my D drive.

Easy:

1. Install Ubuntu according to the standard instructions


2. When you come to item number 8, take advanced partitioning and set the grub boot drive to SDB in MBR mode


3. continue a normal installation

Now, when you want to boot into Ubuntu, set the boot drive to /dev/sdb (probably PLEXTOR in your BIOS) and boot off there!