OK. You have the latest kernel for 5.2. If you want the gcc compiler do:
but you may find out you need more tools. If so you can go for the bigger installation of:
yum groupinstall development-tools
When it says you need the kernel source, the likelihood is that it needs the devel package and possibly the headers which you can install with:
yum install kernel-headers kernel-devel
You may want to just try the devel first. I had a look in the repo's yesterday and could not find the source code so try this first.