What is the ruling of the Shari'ah regarding the accident that occurred and what the questioner is required to do, given that his speed was close to 60 km/h, and the other party claims it was 80 km/h?

If the liability arises from exceeding the specified speed limit (60 km/h) in a place where driving at such a speed is considered negligent, and it has not been proven that the questioner exceeded this speed, then he is not liable, because the default is the exoneration of his liability. However, if he predominantly believes that he exceeded the specified speed, then he is obligated to share with the other party in covering the damages; because predominant belief is akin to certainty in most rulings.