Air Law and the GCAA Regulatory Framework
Where the rules come from
The Chicago Convention (1944) rests on Article 1: each State has complete and exclusive sovereignty over its airspace. Its 19 Annexes contain Standards ('shall', binding unless a difference is filed) and Recommended Practices ('should'). The PANS documents - PANS-ATM (Doc 4444) and PANS-OPS (Doc 8168) - hold the operational detail (separation minima, phraseology, cruise climb) and become binding through State adoption.
The UAE GCAA administers the Civil Aviation Law and the Civil Aviation Regulations (CARs), which adopt the ICAO Annexes and add national requirements. Advisory material and guidance publications explain the rules but are not themselves law.
Licensing
Annex 1 governs ATC licensing: ratings (aerodrome, approach procedural, approach surveillance, area procedural, area surveillance), unit endorsements, a Class 3 medical, English language proficiency at ICAO Level 4 or better, and a competency assessment before privileges are exercised. A rating without a valid unit endorsement does not authorise you to provide the service unsupervised.
Traps
Know which Annex does what: Annex 2 rules of the air, Annex 10 communications/navigation/surveillance, Annex 11 ATS, Annex 14 aerodromes, Annex 15 AIS, Annex 19 safety management. Questions swap Annex 10 and 11, or present guidance material as if it were binding. Another favourite: quoting a 'should' as if it were a mandatory Standard.
Rule of thumb
Read the verb. 'Shall' = Standard, 'should' = Recommendation, 'may' = discretion. Any answer that contradicts the verb is wrong, however sensible it sounds.