Hi, absolute newbie to all things DIY here!
I'm wanting to paint my fence but have noticed some rust scattered on the bottom of it and parts of the centre, can I still paint it? I will have to replace the fence at some point but right now that's not a financially viable option for me, hence the paint job - but I have no idea where to start.
Can I treat the rust somehow, apply a primer and then paint? 

Thank you!