Someone more knowledgeable (or awake) than I am may be able to offer much more or correct me if I’m wrong, but since I see you’ve had a dozen views over 18 hours and no responses, let me offer you what I can. 
Disclaimers up front: I haven’t used BitLocker personally, and I’m just waking up. Either of these might cause me to say something very silly; if so, I apologize! However, I have dual-booted Windows and Linux at many points over the last two decades or so, and my desktop currently dual boots Windows 11 (without BitLocker) and Fedora, so I do have some idea of what I’m talking about.
I understand BitLocker to be either partition or full disk encryption (I don’t know which) with the key stored in your system’s TPM (fTPM in your case, I believe) so you don’t have to enter it at boot. Wikipedia calls it “full volume encryption”; I’m not 100% sure I understand the difference between volume and partition in this case, but since you’re presumably not using logical volumes to do advanced things with storage (like join multiple partitions on different disks), I’m guessing that you can think of BitLocker as encrypting individual partitions.
Based on this (possibly mistaken) conclusion, I do not think that BitLocker will not interfere with setting up Fedora on a second SSD. Even if I’m wrong about the encryption type, as long as you don’t ask BitLocker to interact with the Fedora SSD (e.g. by setting up a Windows partition for some extra storage), I’m guessing that it will leave Fedora alone. So, storage-wise, I think you’re okay.
I don’t know how to set up Fedora with TPM-based encryption, but please be very careful not to do this! To the best of my knowledge, TPMs do not support dual booting. Windows expects to own your TPM, so leave it be. If you want to encrypt Fedora, configure it (LUKS, I presume) to request a password from you on boot.
The second part of your question is about how to dual boot. I would do this either of two ways, depending on preference: UEFI boot selection or GRUB. You can absolutely use both at the same time, and I have occasionally found utility in doing so.
UEFI boot selection is always available to you and requires no extra setup (unless you go messing with UEFI boot entries, e.g. with efibootmgr on Linux, and mess something up). I don’t recall how Framework laptops work in this respect, and I can’t check, as I’m typing on my Framework 13, but when you first turn on your PC, you should have an option to press something like F12 to enter a boot options menu. From there, you can choose which boot loader (EFI image) to load. If you pick the Windows one, you boot to Windows; if you pick the Fedora one, you boot to Linux (after possibly seeing the GRUB menu). If you want to mostly use one or the other, feel free to configure a default in BIOS and then rely on this boot selection screen when you want to pick the other. This makes the non-default OS invisible unless you look for it.
Brief note: I think you might be able to configure the Windows boot loader to display a menu and let you boot to Linux, but I have never tried doing this.
On the Fedora side, GRUB can be configured to run os-prober, which should find Windows and add an entry in the GRUB menu to boot to it. Getting GRUB to actually do so (if it doesn’t by default) is a small rabbit hole that I won’t try to document here; if you haven’t done it before, IMO it’s a great learning experience for Linux, so I encourage you to try it! Just please exercise care (e.g. read the docs before you type and check what you typed before you hit Enter). Most things you mess up are probably recoverable, but said recovery might be a different rabbit hole. When you have the BIOS configured to boot to Fedora and GRUB configured with os-prober to find Windows, you’ll be able to pick between Windows and Linux on each boot by choosing from a text-based menu.
However, there’s a caveat on Fedora. (I’m on 42; I think this applies to 43 but can’t say for sure.) Fedora 29 introduced a GRUB customization to hide GRUB if the last boot was successful (e.g. after the system has been up for 2 minutes, IIRC) and didn’t document this properly (AFAICT). Ahem, ask me how I know…. Let me save you hours of headaches by pointing you to the HiddenGrubMenu change proposal and the author’s blog post. Please do take a look at these rather than uncritically running code a random person on the Internet hands you. Having said that, the TL;DR is, run this as root to disable the feature: grub2-editenv - unset menu_auto_hide. After you do that, I think you’ll have a happy time.
If you do go the GRUB route, I’ll mention that I personally like to customize it to place Windows above Fedora, mainly because it lets me use muscle memory to pick between Fedora and Windows. Without this, Fedora’s entries for old kernel versions push Windows down the list. (I then also set Fedora as the default via GRUB_DEFAULT=1). In /etc/grub.d, I mv ??_os-prober 10_os-prober and then mv ??_linux 11_linux. After that, remember to update GRUB.
Happy dual booting!