You can talk to someone without finding their posts to reply to by typing an @ symbol and then write the letters of their name without a space to reply to them.
You cam click on people's profiles to learn about them.
You can link a post by copying the address of the post and the pasting it onto your post.
You can click the top of the screen to go to the home screen.
You can post pictures by going do you documents and dragging the picture onto your post.
Is there anything else you want to know?