Yes, it can be expensive to go to Disney. The trick is to find ways to save money (free dining plan, etc.).
You can create a savings account with your local bank or credit union. Making sure to put money aside weekly or monthly.
Disney has a great program called Disney Vacation Account. You can use it to save for up to 5 years!! Not only that, it will help you estimate what you need for money for your trip-double win.
Use this Disney link: https://disneyvacationaccount.disney.go.com/?int_cmp=INS-intWDWtoDVA-DisneyVacaAccount/
It’s easier to save a little at a time then to pay in one lump sum. Enjoy!!