If some one is pregnant and the decided to...

will they ask for married situation or cetificate in your case ?
information about being married or not  may be needed in history form , but they are not intended to be shared , as your information is supposed to be confiditional 
- marraige certificate wont be need in this time , but its will be needed in term of delivery 
what to do next :
- just pick any local or private clinic and do the needed tests 
are you legally accused in something in this case ?
no you are not 
General advices during pregnancy : 
1. See your doctor regularly to check on your health and your pregnancy 
2. Get enough rest
3. exercise regularly
4. avoid smoking and alcohol
5. Avoid taking any medications without consulting the doctor
General advice regarding nutrition during pregnancy?
1. eat healthy foods constantly
2. Eat more vegetables and fruits and avoid fatty and oily food 
3. Avoid fast foods and processed food 
4. Drink enough water