If your Mac has never had macOS 10.13+ installed, then you must find an original Apple SSD compatible with your exact model of laptop so that you can install macOS 10.13+ to the internal Apple SSD. There is no way around this requirement since the firmware updater found within the macOS 10.13+ installer requires a properly formatted & working internal Apple SSD. Keep in mind some other Macs may use a similar SSD with the same pin connector layout for the SSD, but they may not work in your 2015 MBPro since macOS can recognize the SSD is not compatible and may refuse to work at all. I have personally confirmed all of this with direct personal experience and experimentation.
If you already had macOS 10.13+ installed on this laptop, then in theory you should be able to boot into Internet Recovery Mode using Command + Option + R in order to install macOS 11.5 Big Sur. However, unfortunately some Macs will still default to booting the original OS which shipped with the laptop from the factory.
If you already had macOS 10.13+ installed on this Mac and Internet Recovery Mode is not booting to macOS 11.5 Big Sur, then you can in theory create a bootable macOS 10.13 recovery mode USB installer which mimics Recovery Mode, but you need to have access to the macOS 10.13 installer so that you can extract the necessary boot image which is possible using Linux. However, it is much easier if you have access to another Mac which is compatible with macOS 10.13 to 11.5 in order to create a bootable macOS USB installer using the instructions in this Apple article:
How to create a bootable installer for macOS - Apple Support