As already mentioned here, there are a lot of old, existing threads with masses of information to wade through and an amazing amount of talented, approachable people here to offer help and advice.
I wouldn't say one stringed instrument is any easier to learn than another (it isn't about the number of strings) but if you have a fancy to play guitar, don't buy an expensive one but equally don't buy the cheapest. Get a guitar playing friend (everybody's got one) to go with you and get a standard, factory produced entry level guitar (£100?),I could start naming names but it's not too important given the very high standards of guitars today.
You will need to learn the names of notes and chord shapes and eventually scales etc, but it's important that you learn one or two simple songs early on to give you something to sing along to and get your strumming hand working properly. The songs don't matter, xmas carols, nursery rhymes, whatever, as long as they're familiar to you so that you start to generate a rhythm and get your hand used to making shapes in time.
I hope you take it up, age isn't important and making music at any level is a very fulfilling activity.
Good luck.
C-flat.