Get unscared and do what needs to be done. Or wear pads. Or talk with your mom or a school counselor. The box has excellent instructions and it's extremely easy and comfortable.
Finally, absolutely nothing to be scared of. Nothing.
I'm too scared to put a tampon inside of my vagina...what should I do?
I think you should consider wearing adult diapers instead! I'm sure that everyone knowing you wear adult diapers will make you VERY POPULAR among your peers!
You don't HAVE to .. It's a matter of personal choice. It's only an alternative for a pad.
If you are scared then stick to sanitary pads, they are much better designed now than they use to be, the wings stop them from shifting about, you also have a night-time option.
When you are ready then try tampons, there are plenty of videos online of girls trying them and tips, you are not alone in this internet age.
There are also plenty of links, but really it just boils down to practice, best to try a tampon for a lighter flow the first time, and only practice when you are on the heavier phrase of your period, as putting in and pulling out a dry tampon can be uncomfortable. This link looked informative:-
You previously indicated you have a diagnosed phobia. And given some of your answers to other questions, as well as what you reveal about yourself in this question, it seems like you have more anxiety in your life than is typical.
Talk to your mom and dad about this. Many people have excessive anxiety due to an imbalance in their brain chemistry---and there are lots of good medications to balance things out for you.