Affiliate ad's hmm?

Hello everyone 3 things if you can help me

1 I'm not from the US or in the US can i make $ with ads and affiliate ?
2 If i put the link and the ad's on other sites forums classifieds spam
or do i need to have a site of my own?).
&
3 some good sites that pays best if you can give me
Thanks in advance

You can make money as an affiliate if you're not in the USA. There are networks out there that accept non-US members. Most of the time it will be considered spam, but most forums have a category where you can post your affiliate links and it is not a problem. Just make sure you read their terms and rules first.