What Does The Following Ultrasound Report Indicate?

Hai I have a single fetus and is lie in longitudinal position.Presentation- chephalic, Fetal spine- rto anterior,Placenta- low lying and ends 1.0cm proximal to internal Oscar,Position- posterior Maturiy- o grade AAsiatic fluid- adequate Fetal anomaly- no lethal anaomalies seen Impression- single live intranet uterine fetus of 20-21 weeks gestation. Kindly suggest for the above scan report. Is it very critical position.Can I have to do normal work or have to take complete bed rest. What type of food I have to eat.