The most important part is how they are set up !
Make sure that husbandry (heat/humidity/hides) is 100% correct.
Keep them in a SMALL enclosure at first, make sure that enclosure is covered on the back and sides and top, to make them feel safe. Add a small hide (just big enough to squeeze in) for them, so they can feel even safer.
If they are set up correctly, try feeding after they had at least a week to settle in, without any handling or stress.
If they don't go for it, wait 3 or 4 days, try again. Try late evening/night.
Good luck
And yes, they can go a long time without food, assist (or worse, force) feeding should be absolutely the last resort, when it is between that or the snake dying of starvation.