A true friend is caring & honest with you.
When you ask for advice, s/he will tell you what s/he feels is true -- not necessarily what you want to hear. S/he will be compassionate, empathetic, and supportive too. Plus enjoy fun activities with you, & show up when s/he says s/he will! to have a friend like that, you need to be one also. Friendships take time & ongoing experience to build.