tractor transmition

hi folks,

i want to buy a tractor for using a snow blower but i relly like to know how stuff works befor getting involve with this, i know backhoe excavator skidsteer hevy truck but the tractor betewwn the engin ant the rear end is a total mistery for me how can you use the pto a 1500 rmp or so and shift gear ? or even switch direction t am not talking cvt ou hydrostatic those i understant but some 16 speed powershift i have no clue on how that works

and how hard it is to repaire i did a shutlle job on my 580k backhoe that was fairly easy ther is a drive shaft but i see some tractor split in 2 to change a clutch ???

thanks four your time sorry for my bad englise i am a french canadien ;-)

tractor transmition