"Travel" we use when talking about general trips abroad (or if not abroad, at least away from home), e.g.: My favorite thing to do is travel His travels brought him all over the world. He travels frequently for his job. "Tour" in the sense of travel has the sense of complete or near-complete exploration of a place, typically as travel for pleasure: His tour through Europe brought him to France, Spain, Italy, and Germany in the same month. I saw Beijing and Xi'an on my tour through China. "Tour" can also be a guided expedition under someone who knows the place being explored better than those (s)he's leading. This can be on a smaller scale: We paid $20 for a tour through the science museum. . . . Or on a grander one: Perù natives took us on an unforgettable tour of the Andes. Whoever is leading such a trip --- whether it be through the museum, the Andes, or even a continent --- is generally called a "tour guide". "Tour" in general is a just a trip taken around a some definite place; for example, musicians who travel through their countries and abroad are said to be "touring artists" on a "concert tour" (which we typically refer to as just a 'tour'). "Program" and "programme" have identical meanings, but the former is almost exclusive in the United States, whereas both forms appear in Canada and Australia, and programme almost exclusively in the UK. A "project" is something someone sets out to do, that is, something planned, with a goal in mind: Our computer science project is nearing completion. His science fair project won first place. Used as a verb, it can mean to predict: We project lower earnings than expected for this quarter. . . . Or to throw outwards (which is its literal meaning in Latin, as a fun fact), usually in a figurative sense: His figure projected a long shadow on the lonely shore. If you were asking what the relation between program/programme and project is, I would say that there isn't any. They aren't synonyms, nor antonyms, in any sense that I know of. Someone will correct me if I'm wrong, I'm sure. 若有些不清楚，欢迎来问我；希望这对你有点儿用处～