I can't upgrade GLIBC 2.27 to GLIBC 2.2.8

Question

I wanna upgrade to GLIBC 2.28

ldd --version

ldd (Ubuntu GLIBC 2.27-3ubuntu1.2) 2.27

I tried to do sudo apt-get install libc6

but it is still the same version not updating

Ubuntu 18.04.5 LTS

any advise?

Thanks