Hi freedom93,
In regards to your router - your neighbor cannot access your wifi connection if they do not know your wifi password (or haven't been able to figure it out). It is good to have a strong password with numbers, capital and lower case letters as well as symbols.
Keep in mind that mobile devices and tablets compress data and webpages differently than a laptop or desktop computer does. Browsing websites on mobile devices uses a "mobile friendly" format and has a smaller resolution area. You'll notice that some icons are smaller on your tablet or iPhone or not all the graphics you see on your computer appear on other devices. Here's an example I put together using ESPN

I hope that helps to clear things up. If you still have any concerns or questions I am happy to go through them with you and help you out!
🙂Thanks
Amanda