From what I can find in answers like this and this, force damage is a nebulous concept of “pure magical energy”, which isn’t very helpful in answering the question of “what effect does this attack have on the creatures I hit with it?”
Even different spells with the same damage type of “force” have different effects. For example, I usually describe magic missile as the enemy being hit with three (or more) bludgeoning attacks. Disintegrate, on the other hand, still deals force damage but explicitly says that if it reduces them to 0 hit points, they are completely disintegrated.
This problem is in effect at least a small amount with Radiant as well, but Acid, Cold, Fire, Lightning, Thunder, Necrotic, Poison, and any others I forgot are relatively easy to imagine with their effects on living beings.
So.. what is Force damage?