@yezzer that one may be junk. Does it use a standard series of tips? If it did, bin the ones it came with and buy the genuine HAKKO/Pace/JBC tips for the iron even if it cost more than the iron itself. Good solder? Try Kester 63/37 “44”. Do you have brass wool tip cleaner? If marginal power, a wet sponge may be cooling your iron too much (and smells bad). After that just practise. Always apply solder to the joint not the tip. More flux is never bad as long as you clean it off when done.