Problems going back in to gear after..

Sorry I hd not be on for a spell, health issues but today i was at the transmission place and he was saying something about the "bronze".... gears? That may need changing.
Many times when I put the car in reverse you hear it grind like it's not going in or goes in but makes the sound.
Lastly the problem with it not going into 1st or second was when it gets a little hot I wanted to make sure the tranny had oil abs that's why I was there and it's full.
He said it's the gears of in not mistaken, 3rd had problems last year but it's slowly becoming to other gears... at low rpms it will go into 3rd much easier than if I m at 5 500 rpms... but it will miss 3rd at times at regular speeds as well but not as often.
Thank you guys