Fatima is a fairly quick bus ride from Tomar, ha hour and a half or so if I remember correctly. Fatima is worth seeing. They do not charge see the church as many other places do. The gigantic plaza between the other buildings is a great sight. Just imagine it full of pilgrims. I did not stay for the candlelight procession, but people tell me it is beautiful and touching. I did walk by the area where people light candles and pray. The amount of wax flowing is incredible. They have vacuums to pick up what has missed the drain.
If you are walking from Tomar to Porto, to me that was the worst day of my Camino from Lisbon to Santiago. I did not start until 10 as I wanted to walk to the Templar castle in Tomar first. The walk from Tomar to Cortica was hot and hilly. I think there should be a plenary indulgence awarded for walking through eucalyptus forests on a hot day. They suck the air out of you as you are trying to breathe it in. Also, a lot of the path skirts the towns, so there is not much water available. I saw a firend eating a popsicle at a bar at the top of the first steep climb out of Tomar. I kept going which was a big mistake. I finished my water and figured I would pass a town. The trail was always on the outskirts of them. I was literally staggering when I saw a man working on a house. He offered me water. He did tell me that he was making the house into an albergue since there were such long distances there without water. After that, the next place to get a drink was a gas station about 150 meters away from where the camino crosses a highway. If you are walking, take plenty of water.