Go for it Dave, I've been using one for years, this one is a 3B+ and it does everything I want, although it runs out of memory when I watch YouTube in multiple windows.
It uses very little power, you can power it from AA batteries but it's a bit fussy about mains power, get the genuine power supply not a generic one.
I use a USB keyboard and mouse but it will quite happily run a Bluetooth one if you need all 4 USB ports for something else.
There's lots of info on their website plus free updates and OS.
www.raspberrypi.org
Mick