Before providing you with an answer, we will need some more information; are you experiencing the somewhat common issue where the iPod will show that the headphones are plugged in even when they’re not? No audio with any kind of headphones? Have you tried using a Bluetooth connection or connecting it to a speaker with an auxiliary cable?
For preliminary troubleshooting: make sure the iPod is up to date, then dip a Q-tip in isopropyl alcohol and use it to clean the headphone jack and the lightning port. This will clear any overt corrosion and get rid of debris. If updating and cleaning don’t work. Let us know! There’s more troubleshooting to try.