The bread in the bakery is soft mainly because a lot of oil and improvers are added. If you want to do this, you can try adding more butter, lard or salad oil peanut oil. The more oil, the softer it is. Or try to buy bread improvers.

This is not a good thing. I suggest you not pursue this goal. Authentic European bread is so hard and healthy.

If you just want to improve it slightly, you can add a small amount of water or milk and eggs to the original formula, or you can make some improvements, but it can't reach the softness of the bakery.