CRS switches, running RouterOS, are L3 devices.
The way VLANs are configured on CRS3xx is very well described in this tutorial.
Beware: CRS, being L3 device, will route between all interfaces with L3 setup (e.g. VLANs with IP address set). If you want to run DHCP server for some (or all) VLAN, that VLAN will need corresponding IP address set and will thus become candidate for routing. If you want to use upstream router for routing, you’ll have to include some firewall filters which will block inter-VLAN traffic.