Everything that is written by the prophets about the Son of Man will be fulfilled

Luke 18:31
Jesus took the Twelve aside and told them, “We are going up to Jerusalem, and everything that is written by the prophets about the Son of Man will be fulfilled. 

Our Lord Yshua had a very focussed mission. From start to finish he knew what He was going to do. However, He always had time for other requests that came up throughout His ministry. Nevertheless, as He reminded His disciples, His mission had already been written by the prophets hundreds of years before. For us today, even though we have a will to choose, God has plans to accomplish His will. We can surrender our wills, just as we surrender ourselves to Lord Yshua and be part of God's will, or we can follow our own course totally separate to God's will. It may be worthwhile noting that those close to Him, will be compelled to follow Him by the Holy Spirit.

After that, He appeared in another form to two of them as they walked and went into the country

Mark 16:12
After that, He appeared in another form to two of them as they walked and went into the country.

Is there a difference between those who see the risen Lord and those who believe in Him by faith. There is a selected few whom the Lord appears to, for the purpose of certain tasks God has assigned them, for example Paul was chosen and the Lord appeared to Him.

However, for most people it is through faith that we believe in Yshua. In fact He regards those people who believe by faith as more blessed than those who have seen Him, because once He is seen, then His existence is confirmed.

On the other hand those who do have the privilege of seeing the Lord are called to another level of mission that others are not be able to comprehend. With this privilege comes greater responsibility.