get the isrgrootx1 root certificate:

curl https://letsencrypt.org/certs/isrgrootx1.pem -o /etc/ssl/misc/isrgrootx1.pem

create the following config in /var/lib/iwd/c-base-crew.8021x

[Security]
EAP-Method=PEAP
EAP-Identity=<id>
EAP-Phase2-Method=MSCHAPV2
EAP-PEAP-Phase2-Method=MSCHAPV2
EAP-PEAP-CACert=/etc/ssl/misc/isrgrootx1.pem
EAP-PEAP-ServerDomainMask=radius.cbrp3.c-base.org
EAP-PEAP-Phase2-Identity=<id>        #dein c-base ldap user
EAP-PEAP-Phase2-Password=<password>  #dein c-base ldap passwort

[Settings]
AutoConnect=true

and connect:

iwctl station wlan0 connect c-base-crew