As others have said, ultimately, either don'f use the car for now, or put the spare/space saver on....

however, in answer to the original question, the tyres withthe least tread on should be on the front & the tyres with the most tread on should be on the rears.

whenever I have bought 2 new tyres for my car, the tyre fitters have always put the new tyres on the rears & rotated the rear tyres to the front.

if you hit standing water or are driving in wet weather, the tyres with the least grip will lose grip first.
so;

If the balder tyres are on the front, then the car will understeer.
If the balder tyres are on the rear, then the car will oversteer.

now we all love a bit of oversteer, preferably on a track, but on ordinary roads, with other road users to consider, then its far, far easier to control understeer.

handy vid to demonstrate: