How many cores do I need for a laptop?

Hello, apology for the dumb question in the header. I've just started working as a software developer. So far I've worked on the backend side, coded in Nest JS and worked with other relevant technologies.

I am in need of a laptop upgrade as my current one gets slow while working. It has only 2 cores. I am confused how many cores I need in a laptop to work properly. I also play games once in a while. Please enlighten me on this issue.

Thanks in advance!