He could not win but learnt a lot. Which parts of speech is the word 'but'?

'He is poor but honest.' _ in this sentence which is conjunction? Tell me _ that. Look before you leap. The word before used in the sentence is— ........ you start now, you will be late. It is health _ is wealth. The main objective of a 'conjunction' is- Give her a telephone number to ring ……… she gets lost. 'He could not win but learnt a lot.' Which part of speech is the word 'but'? Visit you — I have finished my homework. I have read the book _ you lent me.