Como Entrar A Mi Correo Gmail Desde La Computadora

I have just recently switched from an ultrabook to a macbook pro and I'm having some problems since this is the first time I have owned a mac. I have downloaded the latest version of Adobe Flash player but whenever I use safari and try to watch a video on youtube or any other website it tells me that I need to download the latest version of flash player. This only happens when I use safari, it works just fine on chrome. I have restarted my computer several times but that doesn't do anything. I have installed and uninstalled flash player several times but that doesn't do anything also. I have checked if the flash player plug-in is on my internet plug-ins folder and it is and the internet plug ins are not blocked on my safari preferences. This isn't the frst time that this has hapenned to me, when I first downloaded flah player I had the same problem but unfortunately I forgot how I fixed the problem. Does anyone know how to fix this problem, I'm getting really annoyed by this since I never had this kind problem with my old ultrabook. Any help would be greatly appreciated.