'How many different meanings can 'ut' have?'

Ut can be used with either subjunctive or indicative 'normal' verbs, or without a verb altogether. With indicatives, it tends to mean 'when', so for instance 'surgit ut milites movent' would mean 'he rises when the soldiers move'. Without a verb, it usually means 'like', so 'ambulat ut leo' would mean 'he walks like a lion.
With a subjunctive, ut can introduce two types of clause, a result clause and a purpose clause. A result clause denotes a thing happening in consequence of the main clause and usually has in the primary clause a word meaning 'so great' or 'so many' (e.g. tam, tot, tantum). So if you have the sentence 'TOT milites sunt ut omnes PAVEANT' it would mean 'there are so many soldiers THAT everyone's afraid.' So in that situation, 'ut' tends to mean 'that'
A purpose clause is one that shows the purpose of the main clause, so the 'ut' usually translates as 'to' or 'in order to'. For example, 'Ad Olympiam venit ut pugnet' would mean 'He came to Olympia to fight'.