phosh gives me an error and phoc opens up empty black screen or few apps which I try to open hence onwards

As far as I know pho stands for phone I think,- When I run phosh I getting following error :~$ phosh (phoc:9139): phoc-wlroots-CRITICAL **: 16:28:35.127: [libseat] [libseat/backend/logind.c:131] Could not take device: Device or resource busy (phoc:9139): phoc-wlroots-CRITICAL **: 16:28:35.127: [backend/session/session.c:322] Failed to open device: '/dev/dri/card0': Resource temporarily unavailable (phoc:9139): phoc-wlroots-CRITICAL **: 16:28:35.127: [backend/backend.c:217] Found 0 GPUs, cannot create backend (phoc:9139): phoc-wlroots-CRITICAL **: 16:28:35.127: [backend/backend.c:311] failed to add backend 'drm' (phoc:9139): phoc-server-CRITICAL **: 16:28:35.151: Failed to create server: Could not create backend and phoc opens up blank empty black screen or it opens up the few of the apps whatever I try to open after, for example eclipse ide while I close phoc window, I get the following terminal output phoc-output-Message: 16:32:20.323: Output 'X11-1' added ('The X.Org Foundation'/'11.0'/''), 0mm x 0mm I would like know what is use of this phoc and phosh