in other words, a computer that can only run 32-bit OS is very likely too under-powered to do real-time video encoding without a LOT of sophisticated configuration of OS & OBS Studio ... and, I don't mean to offend, someone with that expertise wouldn't have posted a question like this.
If just recording the screen, and it has to be on that ancient computer, you'd probably be better off using native OS tools (ex Windows Recorder). Then video edit on a more powerful computer. My primary computer (workstation class machine, with upgrades) until a few days ago is almost 15 years old. And it runs 64-bit Windows desktop OS... which I've been doing for 20+ years. BUT, that PC was NOT used for real-time video encoding work.. simply wrong tool for the job.
If what you are looking for is something that combines screen + video (/web)camera + and maybe an overlay... realize how computationally demanding that is. The real-time video encoding can be offloaded from CPU to a dedicated video encoding chip, but does your old computer have that? if would it work at the resolution you want? sorry, but things get technical and 'it depends' quickly