you right click on a block
right mouse click
A clock in Minecraft is a handheld item, it can't be placed like a decorative block. However what you can do is craft an Item Frame and put that on the wall, then put the clock on the item frame. That way you then have a wall-mounted clock.
Minecraft's Item ID's can be found on Minecraft Wiki. Link in related links.
Yes. Slime ball, enderpearl, eye of the ender... but you can`t place any of them.
No, you can't take one item from a Minecraft mod unless there is a separate mod which contains that one item.
If you have a 2 button mouse it will be the right button. Just click it once for one item.
first you select the block or item you want to place out of your inventory , then simply click where you want to put it.
Minecraft
The item ID for a diamond pick in Minecraft is 278. I have linked you below in the related links of a full list of all the ID's in Minecraft.
You can't.
No
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