2003 Skoda Octavia takes time to accelerate

In the morning when i start the car If I dont accelerate a little the engine will turn off and sound like it would give backfire but it's not showing any .And after 2 try , it will keep running. But when I accelerate you can here the engine aspirating the air before taking the rev-up . If it push it down the floor it does the same like it will cut off but after 1second approximately it accelerate. Its annoying specially when going up hill after a complete stop . I have to pull the brake while accelerating until I feel a little torque to move the car . so far the garage cant help me
How can I solve this please .?