can I delete old iOs version on my Mac to make some place in my drive? and keep/install the newest one?
MacBook Pro 13″, macOS 10.15
You only have one OS. Old installer files are basically useless.
You don't generally install a newer OS on a functioning machine, you upgrade to it. Whether or not you can do that depends on what OS you have and what year your Mac is.
Your info says you're running OS 10.15. That puts you four full OS versions behind. You don't say what year your Mac is but with an OS that old I'd assume the Mac is old too. Old age will restrict which newer OS you can upgrade to.
