The D7100, D7200 and D750 built in flashes all work in “Commander Mode” to control off-camera flash units. The Z50 does not have that mode unfortunately.
Optically controlled remote has given way to radio controlled remote flash triggering for many reasons, range and reliability among them.
If Nikon’s radio system seems expensive then Yongnuo and Godox make workable systems for much less.
Todays “Eneloop” style rechargeable batteries hold their charge for many months without use. This reduces the occurrence of dead batteries when you need them the most.
if you have not tried a modern radio flash controller, you should. I find their usefulness and reliability to far exceed the old optical style.
There is no argument against the convenience of the Commander Mode on a built in flash though.