If you click on the Shield Icon, in your profile that's in the upper left of your screen, you'll be able to access a list of Fellowships. You owe yourself the benefit of wading through the profiles of the various Fellowships, to ensure that you have mutual interests.
Some of the Fellowships will allow you to apply, while others will prefer that you first send them a message. There's no need to jump on the first horse that runs by; take your time, and find a good fit.