When a company “deprecates” something, it means that they won’t put any more resources into developing it. They will usually continue to support it. Sometimes that support has a clear end date, sometimes it does not. As a fairly famous example, Microsoft deprecated the SNMP feature quite some time ago, but you can continue to install and use it in their current operating systems.
Importantly, “deprecated” DOES NOT mean “removed”. You can continue to use deprecated features, but the company or developer has effectively put you on notice to start looking for alternatives.
Do not confuse “deprecate” with “depreciate”. “Depreciate” is an accounting term that deals with the reduction in value of an object.