In Metropolitan France, they tend to be pronounced exactly the same, and you would have to go by the context. To hear a more traditional pronunciation of the two words, you should talk to a French Canadian.

Then there are other sounds that you don't have to pronounce in french like the d sound or the t sound that just come by the ending of the word ( ex ( to understand or to comprehend : comprendre ) je comprends, tu comprends, il comprend .. for all these several conjugation the pronunciation is the same : " compron " the difference is only in the first part where you add je or tu or il! So what I have to say the best way to get fluent at french and figure out how to pronouce these verbs and nouns with silent sounds is to watvh french tv programs ! Good channels would be : france 2, france 3, france 5 , tv5 monde, M6 , NRJ and others

Yes je serai sound the same as je serais it is simply because the "s" for verbs or nouns or all of that in french are not pronouced ! ( exp. Une chose ( one thing ) " pronunciation une choze " des choses ( a lot of things ) " pronunciation dé choze " I mean for both of je serai and je serais the pronunciation would be the same like you've already mentioned " je seré "