From the main rule book (pg. 19), each pony should start with 1 token per player (including the GM):
Your level 1 pony character starts with 1 Token of Friendship per
player in the group, including the gamemaster.
Friendship is probably the most valuable of your abilities - Tokens of
Friendship allow you and your friends to get out of trouble - but once
you use them, they are gone for good.
On page 48, it describes how you can not only earn more tokens, but that you can combine your tokens with those of your fellow players to achieve effects:
Mixing Tokens of Friendship
There's one more thing that you should remember - whenever you are
using Tokens of Friendship, you can mix them with Tokens from your
friends, and the more you do this, the more powerful they become!
It goes on to mention that the GM should adjust the amount of tokens required to achieve an effect downward if more than one player are combining tokens:
To continue our die roll example, the gamemaster might decide that if
both you and a friend use a Token of Friendship on a roll, those
Tokens count in total as three Tokens instead of just Two.
And lastly, page 48 and 49 go in to how to earn more tokens during play:
Whenever you level up, everypony gains a number of Tokens of
Friendship equal to the number of friends they are leveling up with.
Another way of earning Tokens of Friendship is for your pony to behave
as a very, very good friend to their friends, particularly when they
are in need [...] The gamemaster should always reward acts of great
friendship with free Tokens of Friendship for the pony character
acting in such a friendly way.
And, one last way to gain tokens"
Whenever a new friend joins the group, one Token of Friendship is
immediately added to each player's pool - the more the mare-ier! When
a friend leaves the group or cannot make it to a game session, the
group members do not lose a Token of Friendship, since that person
is still a friend in spirit, even if they cannot be there in pony!
How do ponies get more than 1 friendship point? They start with them (1 per player, so at least 2 and probably more). They can also earn them in game by being a good friend.
What does spending mean? Do they just leave the game, or do you give them to another pony? They are gone for good - they leave the game.