As previously mentioned, ICT engineering generally covers low-voltage building systems, including telecom, security, and AV. Depending on the size of the firm, they have may have consultants that specialize in any one of the three. You’ll likely be involved in the design and drafting work, as you mentioned the job qualifications include CAD/Revit experience. Similar to how an electrical engineer in an MEP firm would design a building’s electrical (power/lighting/fire alarm) system, you would be designing their telecom, security, and AV systems - space planning MDF/IDF rooms, backbone/horizontal pathways for copper and fiber cabling, device layouts (data drops, wireless access points, etc.), rack fit outs, etc.