It appears you've set it to start up on the Image Editor window.
In the bottom left, there's a small box that allows you to change the current editor type. Select
Select the box(I highlighted Highlighted with red) and select the window 3D View.
Then click on 3D view.
Afterwards, before touching anything at all, press CTRL + U and select the option that appears, to set this as the new startup scene. it should be fixed now.