Welcome Ubuntu Global Jammers!
Thanks for taking the time to check out tasks for Ask Ubuntu. We've put together a list of things that should help you get started.
and then submit an edit, then it will go into the queue and you'll earn 2 points for each edit. Once you feel comfortable how the site works you can start to tackle answering questions. Of course, if you're new to Ubuntu you can participate just by asking questions to things you want to know!
Some of the tasks require certain amount of points (to weed out spammers), so just submit a few edits to get the hang of it and then you should get enough points to start to be able to do things like attaching screenshots.
You should check out the FAQFAQ if you've never been here before, and feel free to pop into chat if you need help.