Hi @mpraturi,
Welcome to the community 
We’ve decided it’s best to focus our upgradeability efforts on the Upgrades Plugins exclusively, and have halted development on the OpenZeppelin CLI (formerly known as zos). See: Building for interoperability: why we’re focusing on Upgrades Plugins
If you are creating upgradeable contracts I suggest using OpenZeppelin Upgrades Plugins for Truffle and Hardhat: https://docs.openzeppelin.com/upgrades-plugins/1.x/
If you are creating non-upgradeable contracts then you can use Truffle or Hardhat: See: https://docs.openzeppelin.com/learn/developing-smart-contracts
Out of interest, why were you trying to install zos?