To get or set in environment variables the platform information of a system you can use the following:

export ARCH=$(case $(arch) in x86_64) echo -n amd64 ;; aarch64) echo -n arm64 ;; *) echo -n $(arch) ;; esac)
export OS=$(uname | awk '{print tolower($0)}')

Taken from the installation instructions of the Operator SKD here: https://master.sdk.operatorframework.io/docs/installation/