Yes you can use synthetic oil in a 97 Escort.
In the oil pan
The 97 Escort should have 5-30 oil.
Yes you can change to conventional oil.
Unscrew it from the block.
SM rated 5W-30 weight of oil.
It is 4 quarts of oil. As well as a 1997 2.0 liter ford escort. Someone said it was 4.5 quarts that is wrong.
4 quarts
Ford recommends 5w30 to be used. There are no recommendations as far as synthetic vs conventional go.
According to the 1997 Ford Escort owners manual ( 5W-30 ) certified for gasoline engines
5W30 is recommended for all temperature ranges
With engine oil filter change ( 3.8 liters / 4.0 quarts of engine oil ) for the 2.0 SPI engine in a 1997 Ford Escort according to the Owner Guide
5w30 fully synthetic and 4.5 litres without filter