How do I reinstall software on a MacBook after erasing it?

AwwDee wrote:

Daughter erased her MacBook and is now struggling to re install a software onto it, gives her the option to install a newer software but it won’t work

she’s done shift cnt option r and it’s still giving the new software ….. what can I do

I'm not certain if that's what you described, but if you want to reinstall that Mac's originally installed operating system (or the one closest to it that remains available) you need to use the key chord described in How to reinstall macOS - Apple Support:

• If you used Shift-Option-Command-R to start up from Internet Recovery, you might get the macOS that came with your Mac, or the closest version still available.

The reason Apple uses the weasel word "might" is not entirely clear to me, but that is as close as you're going to get with that document. Otherwise, provide that Mac's exact model designation, or identify it in some way because there are many MacBook models. Please don't post serial numbers.