Can I know how to save?

There are large green statues with little stone 'doors' where you hit the circle button when you're in front of them and it'll ask you if you want to save. There's also one in front of the temple up the stairs in the center but it's built into the wall so it's easy to miss!(I did for the whole first two times I played...) Usually it glows every couple of seconds and has ivy around it.

All throughout the Forbidden Lands there are shrines. Parts of these shrines glow, if you walk up to the glowing part and hold the 'circle' button a menu will pop up allowing you to save your game. The most prominent shrine is the Shrine of Worship, which is the "castle" you start in. To save at the Shrine of Worship, go to the front, there you will see stairs on the left, the right, and in the middle. The shrine is at the top of the middle staircase.