If you are connecting two network devices then all frames passing between them will be on the same VLAN UNLESS you add additional VLANs, and to have more than one VLAN on a link, all additional VLANs must be tagged.
You need to match tagged VLANs on both ends of a link.
Some switches force you to have one untagged VLAN, some allow you to have only tagged VLANs.
Ideally, don't use an untagged VLAN to pass traffic between two network devices. And ideally, don't use VLAN1 for anything.