While eating food with a fork and a knife, the suggested practice is to hold the fork with the left hand and pick the food with the fork and eat it. But the Sunnah of the Prophet (Sallallahu Alaihi wa Sallam) prohibits eating with the left hand. What is the solution?

Praise be to Allah, the Lord of the World; and may His blessings and peace be upon our Prophet Muhammad and upon all his Family and Companions.

It is unlawful to eat with the left hand using a fork or your bare hand as the Prophet (Sallallahu Alaihi wa Sallam) said: "Say Bismillah, eat with your right hand and eat from what is nearer to you" .
When the Prophet (Sallallahu Alaihi wa Sallam) saw a man eating with his left hand he said to him: "Eat with your right hand". The man said: 'I can't'. The Prophet (Sallallahu Alaihi wa Sallam) there upon said: "May you not be able". He refused (to eat with his right hand) out of arrogance only. He was not able to raise that hand again" .
There are many Hadith proving this. But the solution to what the questioner said is to put the fork in the right hand and the knife in the left hand because the eating should be with the right hand only.
Allah knows best.