Welcome! One of the things I love at Disney for some 'behind the scene's' feelings is either the Keys to the Kingdom tour or the Lunch with an Imagineer dining option.
Keys to the Kingdom - it's 5 or 6 hours and tours the Magic Kingdom. You get a lot of Disney history and a bit of the behind the scenes areas. You'll have a headset so you can hear the guide so you stand out a little less as a solo traveler. We had a few on the tour we went on.
Lunch with an Imagineer - we do the one at the Brown Derby. The food is fabulous and you get to sit with an actual imagineer and they talk about their experiences. Our last group only had 9 people so it was such a nice intimate experience. Again, the focus is so on the Imagineer that it's not noticeable that you are a solo traveler. ( Everyone sits at a big table - executive style ).