Yes, nowadays, machines that come pre-installed with Microsoft Windows always have a recovery partition, from which you can re-install the pre-installed version of Windows. This is because they are no longer shipping an installation DVD with the computer.
Either way, as @dalto says, you cannot have more than 4 primary partitions in a DOS MBR partition table. So if you want to stick with that partition table, then you must replace one of the primary partitions with an extended partition container, and then this extended partition container can in turn contain logical partitions.
The better approach however would be to use a GUID partition table, also known as GPT. It is more robust than the DOS MBR partition table, and it can be used whether the machine boots in UEFI mode or in legacy BIOS mode. There are however differences between both boot methods if you're going to go with a GPT.
In the event of a GPT in combination with UEFI boot, you'll need a special EFI System Partition (ESP) of about 512 MiB, formatted with FAT32. This partition is used for storing the so-called
efivars ─ i.e. the entries for the native UEFI boot manager. The ESP must be marked with the "bootable" and "esp" flags.
In the event of a GPT in combinaton with legacy BIOS boot, you'll need a special partition of type "BIOS" of approximately 5 MiB ─ marked with the "bootable" flag ─ but without a filesystem on it, and this partition must be the first one you create.
In both cases, the partition boundaries must be aligned to the (binary) megabyte.
Another thing that's also imperative is that you cannot use two operating systems on the same HDD when one of them is set to boot in UEFI mode and the other is set to boot in legacy BIOS mode, because in that case, the firmware will always boot the legacy BIOS installation.
So you must either install both operating systems in UEFI mode (and with Secure Boot disabled), or you must install them both in legacy BIOS mode.
P.S. 1: GNU/Linux does not use drive letters, because it is a UNIX system, and UNIX approaches disk storage in a different manner. Drive letters are specific to Microsoft Windows, and were inherited from the original CP/M system by way of DOS, and then later, OS/2.
P.S. 2: You'll need at least two partitions for GNU/Linux itself, one being a root filesystem (
/) and a dedicated swap partition. Recommended is to have three partitions, being a root filesystem (
/), a separate partition for
/home (where your user-owned configuration files and data will live) and a swap partition.
In your case, given that you have 6 GiB of RAM, the swap partition should be about 8 to 10 GiB. You can get by with less, but not if you plan to hibernate the machine ─ i.e. suspend-to-disk.
Your root filesystem should be at least 50 GiB ─ not that you will be using up all of that after a clean install, but as time passes and you periodically install system updates, the downloaded packages will be stored on-disk by default, and then that quickly runs up to quite an amount of space. You must never allow the root filesystem to fill up, because then you'll be in bigger trouble.