Is it possible to use normal tactile buttons as controllers?

Hey there! I found your project interesting so I built the emulator on my raspberry pi pico. I didn't have any have any idea about ZX spectrum until just now, I thought I could use tactile buttons as controller. But then I saw it wasn't working. So I searched about ZX spectrum and realized I had to order PCB for that. But I'm somewhere in the world where custom PCBs are rarely produced and costs a lot. So, is it possible to make tactile buttons on breadboard work too?

Thanks a lot for reading :)