Can someone please help me!

I have wrote y'all before cuz I feel like I'm not smart enough for school to be a RN all I really know how to do is write and read I want to learn more before I start to school to be a rn is there any basic course I can take online to learn how to do math and etc like things I need for RN school ? Cuz I didn't learn it in high school and I don't wanna go in to be a rn and not know how to do anything please help I really wanna be a rn!!

And I wanna go to the 2 year RN program where is a good school around Memphis? Please help with any info I lost my dad not to long ago and I'm tryin to have a good life and help others!