You simply can't do that. WSL doesn't support 32-bit apps!
Most (if not all) Intel and AMD CPUs in the last decade support the x86_64 instruction set and there's no reason for Microsoft to spend time and money on supporting a 32-bit version of Linux. Most developers and Ubuntu users are running the 64-bit version anyway
No, we don’t support x86 32-bit at this time: We currently depend on x64-only instructions and mechanisms to ensure fast & stable performance.
Bash on Ubuntu on Windows
WSL2 runs in a real virtual machine using a real Linux kernel, so it's actually possible to do anything a Linux VM can do, including running 32-bit code. Just install 32-bit libs by running
sudo dpkg --add-architecture i386
sudo apt-get update
But again, you should really opt for the 64-bit version, especially if you have the source code. 32-bit Linux is much less maintained than the 64-bit version, since there are far fewer 32-bit only hardware in the last decade along with a significantly less number of users and testers. One example is that the Meltdown/Spectre patch for 32-bit Linux came out more than half a year later than the 64-bit version, and it's still buggy for years later