IRC stands for Internet Relay Chat.
OpenMandriva is no longer using Freenode IRC. There are Matrix channels for OpenMandriva (user channel) and OpenMandriva Cooker (developer channel). These are also channels at Libera Chat. #openmandriva @ libera.chat and #openmandriva-cooker @ libera.chat. The Matrix and Libera Chat channels are bridged (interconnected). They are also bridged with Telegram.
Connecting with Matrix is described at Chat.
Connecting via Libera Chat is described at Libera.Chat.
Regarding why this change is made, users are encouraged to do an internet search of "Why are Open Source organizations leaving Freenode?" and read for themselves.
The OpenMandriva, or on libera.chat #openmandriva, channel is a great place to ask questions, post tips, report issues, and so forth. Have fun and enjoy OpenMandriva. Please note that people may be in a different timezone than you — if you don’t get an immediate response, stay and wait.
The OpenMandriva Cooker, or on libera.chat #openmandriva-cooker, channel is where developers and contributors communicate about their work with OpenMandriva. Please note that people may be in a different timezone than you — if you don’t get an immediate response, stay and wait.