Having urgent problem while launching PX4 SITL

I installed PX4 SITL by following this - Notion ā€“ The all-in-one workspace for your notes, tasks, wikis, and databases.

Once I try to launch everything, I get these errors -
svrt@svrt-popos:~$ cd PX4-Autopilot/ && make px4_sitl gz_x500
[0/1] cd /home/svrt/PX4-Autopilot/builā€¦topilot/build/px4_sitl_default/bin/px4


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px4 starting.

INFO [px4] startup script: /bin/sh etc/init.d-posix/rcS 0
INFO [init] found model autostart file as SYS_AUTOSTART=4001
INFO [param] selected parameter default file parameters.bson
INFO [param] importing from ā€˜parameters.bsonā€™
INFO [parameters] BSON document size 251 bytes, decoded 251 bytes (INT32:11, FLOAT:2)
INFO [param] selected parameter backup file parameters_backup.bson
INFO [dataman] data manager file ā€˜./datamanā€™ size is 7872608 bytes
INFO [init] Gazebo simulator
INFO [init] starting gazebo with world: /home/svrt/PX4-Autopilot/Tools/simulation/gz/worlds/default.sdf
WARN [init] PX4_GZ_MODEL_POSE not set, spawning at origin.
INFO [gz_bridge] world: default, model name: x500_0, simulation model: x500
INFO [gz_bridge] Requested Model Position: 0,0,0,0,0,0
INFO [gz_bridge] Model position z is less or equal 0.0, moving upwards
ERROR [gz_bridge] Service call timed out. Check GZ_SIM_RESOURCE_PATH is set correctly.
WARN [gz_bridge] Service call timed out as Gazebo has not been detected.
libEGL warning: egl: failed to create dri2 screen
libEGL warning: egl: failed to create dri2 screen
libEGL warning: egl: failed to create dri2 screen
INFO [lockstep_scheduler] setting initial absolute time to 1256000 us
INFO [commander] LED: open /dev/led0 failed (22)
INFO [tone_alarm] home set
INFO [uxrce_dds_client] init UDP agent IP:127.0.0.1, port:8888
INFO [mavlink] mode: Normal, data rate: 4000000 B/s on udp port 18570 remote port 14550
INFO [mavlink] mode: Onboard, data rate: 4000000 B/s on udp port 14580 remote port 14540
INFO [mavlink] mode: Onboard, data rate: 4000 B/s on udp port 14280 remote port 14030
INFO [mavlink] mode: Gimbal, data rate: 400000 B/s on udp port 13030 remote port 13280
INFO [logger] logger started (mode=all)
INFO [logger] Start file log (type: full)
INFO [logger] [logger] ./log/2024-09-14/16_01_37.ulg
INFO [logger] Opened full log file: ./log/2024-09-14/16_01_37.ulg
INFO [mavlink] MAVLink only on localhost (set param MAV_{i}BROADCAST = 1 to enable network)
INFO [mavlink] MAVLink only on localhost (set param MAV
{i}_BROADCAST = 1 to enable network)
INFO [px4] Startup script returned successfully
pxh> WARN [health_and_arming_checks] Preflight Fail: No connection to the ground control station
WARN [health_and_arming_checks] Preflight Fail: No connection to the ground control station
WARN [health_and_arming_checks] Preflight Fail: No connection to the ground control station
pxh> commander takeoff
pxh> WARN [commander] Arming denied: Resolve system health failures first
INFO [tone_alarm] notify negative

The errors -
ERROR [gz_bridge] Service call timed out. Check GZ_SIM_RESOURCE_PATH is set correctly.
WARN [gz_bridge] Service call timed out as Gazebo has not been detected.
and -
WARN [health_and_arming_checks] Preflight Fail: No connection to the ground control station
pxh> commander takeoff
pxh> WARN [commander] Arming denied: Resolve system health failures first

My bashrc already has this - export GZ_SIM_RESOURCE_PATH=/home/svrt/PX4-Autopilot/Tools/simulation/gz

I just donā€™t understand what I am doing wrong. Please help