Hi,
Basically, to have manual installation of any package, it has to be checked whether the package you are trying to update or install has dependencies and if so, you will have to update all of those with it too to avoid any further compatibility issues.
To have manual installation of any package on a RedHat/CentOS machine, you can use their standard mirror to get to the rpm package. You can use the below link and select the OS version follwed with server archetecture and kind of repo you want, updates or all package.
mirror.centos.org/centos/
You can download individual rpm from this mirror to your server and install it using below command:
# rpm -ivh <package_name.rpm>
The above command is like to give dependencies error if the package has dependencies.
If you want to install the rpm with no dependencies, you can use "--nodeps " while installing the rpm with the above command.