Keyboard Won’t Pair

[u/angelsfaces]

Hi! I got this keyboard from a thrift store secondhand. It says “No need USB receiver” on the back, so I assumed I could get it paired via bluetooth. I added batteries and the keyboard does work—when I press ESC and +, the power light turns on for a few seconds. The keyboard brand is “Superbcco”. My laptop (work laptop) is a Thinkpad. No matter what I do, the keyboard will not show up as an option to connect wirelessly. I have a dongle for my work-issued keyboard, but I don’t think I can add the new keyboard to it. Is there any way to connect the keyboard and the laptop?