My mother taught 30-40 girls(4-H) how to sew using two old treadle sewing machines. First she started us off using paper. Put a needle in that machine (no thread), get paper, and sew. Next draw lines on the paper and learn how to follow those. This way you will see how straight you are sewing, if you can follow lines, etc. After you feel confident using the paper, add thread and fabric and practise sewing.
There are many books out there for brand new sewers. Find one and read it, then do it. Or find a friend who knows how to sew or quilt and ask them for help getting started.
Good luck.
Kat