no crank but battery is good

May be starter.

any way to be certain before buying a new starter? is there a way to test it?

I jumped the van left it connected to the donor for about 45 minutes. still nothing. cleaned all the battery term connections to make sure nothing. Starter? Starter solenoid? starter relay? where do i start, no pun intended Thanks

when i jump it and even after there are lights. radio works etc the only thing seemingly different is that it just doesnt crank, when key is turned, there is a whirring sound but no click. wouldnt the engine crank over if the battery was being jumped?