18 was a long ass time ago for me. It would have been the late 90’s. The world was so much different that I don’t think anything I could say in 3 words would make any sense to my 18 year old self. I didn’t have any money at 18 so something like “buy apple stock” wouldn’t have worked.

Even taking the big assumption that I believed what I was telling my 18 year old self I can’t actually come up with anything that makes sense in context. 3 words just isn’t enough to convey anything useful given the time difference and everything else!

I am pretty sure that is NOT a Roman aqueduct but a Portuguese built one from the 18th century.

https://en.wikipedia.org/wiki/Águas_Livres_Aqueduct

https://en.wikipedia.org/wiki/Águas_Livres_Aqueduct#/media/File:Aqueduto_das_Águas_Livres_(1).jpg