An oil change on a vehicle is only needed every 3,000 to 5,000 miles.
If your engine oil has been changed and it hasn't been 3,000 to 5,000 miles since your last oil change then you don't need to change the oil before setting out on a road trip of 500 to 1,000 miles.
However if the oil change interval is getting near and you'll hit the oil change interval in miles when you get out on the road for your road trip then it would be a good idea to go ahead and change the engine oil before the road trip.
However you can also just go to an oil change place and get a cheap oil change while out on the road trip when you get to the oil change mileage.
If it's getting near the mileage to change my oil and I go on a road trip longer than 500 miles then yes I will always change the oil before setting out on the road trip.
You should also check the belts, hoses, tires etc to make sure everything is good to go and check your brake pads or brake shoes and brake rotors and brake drums as well.
Check your engine coolant too and carry extra oil, coolant and even a spare serpentine belt just to be safe as you never know when something can happen and a belt could break if it's old.