Trying to wire a 3 wire dryer from panel box to dryer plug
Sounds like you have a 10-2 NM wire. One black, one white, one bare copper. At panel box, black to one hot terminal of breaker or fuse holder (L1). White to other breaker terminal or other fuse holder (L2). Bare copper to the grounded neutral buss bar.
At the dryer the bare neutral goes to the center terminal, the other two go one each on either side, it won't matter which way. Hot Neutral Hot. The neutral terminal of the dryer should have a wire or metal strap connecting it to the dryer frame if you are not using a four wire supply.