First of all you need new batteries for the TX and the plane. NiMH will do just fine. A bit of searching should find the two packs for 30 -40 $ Try Amazon.
You will need a new glow plug energiser battery too.
You need fresh fuel. This may require a trip to a model shop. These are disappearing fast! Sometimes your closest supplier will be the local flying club. It would be a good idea to visit them with all your kit and I am sure they will help you out especially if your daughter is with you and showing an interest. Junior flyers are rare nowadays.
Your Kadet should still be safe to fly but again the local club will usually have a safety officer who will help you check it over.
Sims are good for training especially those that allow you to use your regular TX or something very like it. I am not up to date with what is available but we do have a sim forum on RCU.
But the very best way to get you and your daughter into the air again is a local flying club with a training program using a buddy box. Use the AMA website to find your closest clubs. I know it is tempting to just find an open space and go flying but if you go down this route be sure to have a big trash bag with you. You will most likely need it on day one.