Red Hat:
RHEL
English:
https://access.redhat.com/support/policy/updates/errata/#Extended_Life_Cycle_Phase
Or:
https://access.redhat.com/product-life-cycles?product=Red%20Hat%20Enterprise%20Linux
Chinese:
https://access.redhat.com/zh_CN/support/policy/updates/errata#Extended_Life_Cycle_Phase
Red Hat all products
https://access.redhat.com/product-life-cycles/update_policies
Red Hat software packages
https://access.redhat.com/support/policy/updates/rhel-app-streams-life-cycle?extIdCarryOver=true&sc_cid=701f2000001OH6fAAG
SUSE:
openSUSE
English:
https://en.opensuse.org/Lifetime
Chinese:
https://zh.opensuse.org/%E4%BD%BF%E7%94%A8%E6%9C%9F%E9%99%90
SLES
https://www.suse.com/lifecycle