Dux.
The English title "Duke" is derived from the Latin word dux, "leader" from ducere, "to lead".
The Latin word for guide is dux ducis. A guide means someone who is a leader, general or a duke.
The Latin word for a great leader is "dux," which translates to "leader" or "commander." Another Latin term for a great leader is "imperator," which means "commander-in-chief" or "emperor." These terms were commonly used in ancient Rome to refer to individuals who held significant power and authority.
Dux Ducis it means Leader, Duke, Guide, and anything else in that category
leader = dux
Erm. As far as I know, there is no direct translation but dux, ducis is close.
Princeps.
Although there is no word for "Chancellor," you could use "Princeps | Princepis" (3rd) which means "Emperor or Leader."
'Doctor' is a Latin word, and means ;Learned Man'. The actural Latin word is 'Doctus'.
Legere is the Latin word which means "to read"
Dux.
The Latin word Carbo means Charcoal