Dual enrollment during homeschooling?

I had to be homeschooled early for medical problems from 2nd grade until 11th. I'm in 11th now and I'm kinda stuck homeschooling. I was considering dual enrolling but I've never took a writing class. I scored roughly 90 on the standford achievement test in english and math. Should I just wait unttil I graduate and take a remedial writing class at a community college or just take a class now and learn writing on the fly?