upgrade from lollypop to marshmellow

[Clairef62]

Hello everyone.
I was wondering if anybody could tell me how i could upgrade my samsung S4-19505 at all please. Thankyou!

 

[PhoneS4]

Hello everyone.
I was wondering if anybody could tell me how i could upgrade my samsung S4-19505 at all please. Thankyou!

Hi! I think your only choice is to install a custom ROM as I did. It may sound complicated in the first place but if you do everything correctly you'll get an amazing phone! There are plenty of guides to install a custom ROM which you can find easily but there are few base things to do:
1. Root your phone
2. Backup
3. Install custom recovery
4. Install custom ROM of your choice (there are many ROMs available, also a Android Nougat ROM which is newer than the Marshmallow you wanted in the first place.