[prashnts]

Cheapest version is 31$. Without internal pullups. Which means it's basically gonna bit-bang if you want to interface with SPI, I2C etc. I'd consider a raspberry pi even if it costs more because it has a _lot_ of I/O capabilities and starts at 5$.

For a comparable option, consider one of the Pi-Picos, Arduinos with VUSB, or a USB-Serial board with extra GPIOS.

[ranger_danger]

Where are you finding raspberry pi for $5?

[dmytrish]

I think they meant Raspberry Pi Pico, which is definitely not a microcomputer with Linux, but it has plenty of I/O pins.