The difference is that the VPS is placed in a cluster and has more limits than the dedicated server, for example the speed is only 100Mbps, on the dedicated server the port is 1Gbps. If you plan that the traffic will increase in the future, I suggest a dedicated server as you have absolutely all the resources of the physical server under your control. The advantage of VPS is that backups are made and in case of any exceptions, you can restore them at any time, which with dedicated servers cannot it is. You must personally take care of the backup on the dedicated server.