On the right side of the motorcycle right under the seat is an oil tank. It will have a chrome plug with a dip stick attached. Read your owners manual, there is a wealth of information in it.
The 883 Sportster takes just under 3 quarts of oil
what type of oil for a 1993 Harley Sportster 883
The drain hose is connected to a nipple underneath the battery tray.
20/50
Sae20W50
should be 20-50 wt harley oil but check with your dealer first..
20w50 motorcycle oil
Under the motor
SAE 20w50 100% synthetic oil.
Three
Should be right at 3 quarts
HD makes a weight of oil they call "Sport-Trans" that is made for use in the Sportster primary. Or, you can use any 30W non-detergent oil.