Hi Xavier,
Juniper ADCX course will be good start which includes all the concepts of IPClos, VCF, EVPN and VXLAN from the basics. Followed by, you can get the JNCIE-DC Self Study Bundle which has concepts of Cos and Security that are needed. Also well packed with lab activities. https://learningportal.juniper.net/juniper/user_activity_info.aspx?id=EDU-JUN-WBT-SSB-JNCIE-DC
For MPLS, Juniper MPLS and VPN's will be a good one to read through. As QFX5100 and QFX10000 will be major part of the lab, recommend to read the O’Reilly series of both of these books.
For EVPN in specific, https://www.juniper.net/documentation/en_US/release-independent/solutions/information-products/pathway-pages/sg-003-evpn-vxlan.pdf is also vey good.
I hope this helps and all the best for your exam.
Regards,
Pradeep Kumar