Yes, and it's one of the most effective fixes there is. Buffering usually means your connection can't keep up with what you're trying to do. When you increase your internet speed, you give your connection more room to work with, so videos load faster, streams run smoother, and that spinning circle shows up a lot less.
That said, speed isn't the only piece of the puzzle. If your Wi-Fi signal is weak or too many devices are competing for bandwidth at once, even a fast connection can struggle. But if you've already checked those things and buffering is still a problem, moving up to a faster plan is usually the answer.
Fybe's 500 Mbps Plan is a good choice for most households. If you've got a lot of people streaming, gaming, or working from home at the same time, the 2Gig or 5Gig plans gives everyone the room they need.