Would anyone be willing to guide me in the right direction? (SSF4:AE)

Ok so iv’e played SSF4 for a long time but ive recently started to go online and get a little more competitive. I just get demolished when i go online by anyone I face online and I need some general help such as characters to use, Strategies and anything useful.
Thanks in advance guys (:

Your post doesn’t give enough information for anyone to help you.

Simplest thing to do is play the character who you like and have fun playing with and as far as losing online just analyze what you’re losing to and work on those things. For example opponent always jumping in, work on Anti-Airs, getting thrown a lot, work on teching, etc.