You need to mind read amdusias for his chest password. You not suppose to go orobas fjords for the moment, eventhough you could do so.
After defeating amdusias, the area which has a barrier in maxos temple will be available to explore, where you need to go to sentinel island to proceed on with the journey
If you had no idea how to defeat amdusias, enter his throne room and run till the middle where you saw some green pile of thing on the ground. Pick up his dragon scale and go into your inventory. Use the orbis arcesso which you get through the quest "twho tomes" and he will be turn back to human form. Then just defeat him and its done.
