You can add as much conditions as needed using elif
func _process (delta):
if Input.is_action_pressed("left"):
$AnimatedSprite.play("walking")
$AnimatedSprite.flip_h = true
elif Input.is_action_pressed("space"):
$AnimatedSprite.play("jumping")
#increase jump velocity
elif Input.is_action_pressed("right"):
$AnimatedSprite.play("walking")
$AnimatedSprite.flip_h = false
else:
$AnimatedSprite.play("idle")
might want to test if the jump animation is not already playing to avoid jumping endlessly