ipv4 and ipv6 are like an indicator for your identity, just like your IC number. When you want to register for something, people asks for your IC number because it identifies you(there's no other person with the same ic as you). So, for a computer to communicate with another computer, it must have an unique ip address so that we know who to send the data to and who should receive it. Why ipv6 is here is because ipv4 is already depleted, so in order to cater for more devices, ipv6 is made.
Benefits:
1. possibly a different routing compared to ipv4, so maybe some websites that don't work that well before
may work better(load faster/download speed is faster)
2. can connect to an ipv6 only website
3. you can connect to your devices on the Internet without having to set port forwarding or whatnot
As for how do you use it, you'll need to check your router on how to enable ipv6, which requires some googling.
Anyway, for normal users it doesn't mean much yet, and probably won't be, until ipv6 adoption is really widespread.
just a question, if i enable ipv6, do i need to disable ipv4? sorry, new to this...tks