Welcome to Gaia.
This site doesn't require the collection of 'friends' to advance in games, so it doesn't necessarily enhance the user experience to ask for friendship from complete strangers.
Get out into the boards and meet people with common interests! Put some effort into it, don't be pushy. Get to actual budding friendship status with someone first before you cement it. Otherwise your notifications sections will mutually fill up with junk that neither party cares about.