You don't need a bridge around your waist, but at least you can put a fist in it.
The grip distance is slightly wider than the shoulder (not too narrow or Sanmao will exert too much force). When pushing, make the angle between arms and torso less than 60 degrees.
2. Pay attention to the angle between the arm and the trunk, and don't do guillotine bench press. When descending, the pole position is 3-5cm around the lower chest.
3. The core of all pushing actions is "clamping" rather than pushing, so if the novice's strength mode is pushing, it is easy to make mistakes. The action of chest training is mainly "clamping", not pushing. Even if you can't, you have to have this concept in your mind.