Hello,
The first question to be answered is your 3rd one. If not solving it before, whatever you could try with TELEMAC and tides is nonsense. TELEMAC needs to know how to interpolate tidal data from TPXO-like solutions with your GEOMETRY FILE.
Anyway, in case you want to model an area around South Morocco, I would recommend your x and y from your GEOMETRY FILE to be built in UTM 28 or 29 (GEOGRAPHIC SYSTEM = 2 and ZONE NUMBER IN GEOGRAPHIC SYSTEM = 28 pr 29), or Mercator projection (GEOGRAPHIC SYSTEM = 5). Otherwise, you have to implement your conversion from your own geographic system to longitude latitude with GEOGRAPHIC SYSTEM = 0 in tpxo.f module. You may have to generate your GEOMETRY FILE with a planned system again.
Rather than using the global solution TPXO, the regional solution Atlantic Ocean may be more suitable to your case, in particular if it is a coastal model:
volkov.oce.orst.edu/tides/AO.html
For your information, people answer to this forum when they have time and asking for an answer quickly (e.g. less than 30 min) may be the best way to never get it...
Chi-Tuan