what to look for in lifting straps and which ones to buy?

so im kinda new to the gym (3 months and something) and i discovered lifting straps and idk which ones to buy,ive seen different shapes,sizes,materials and much more,and idk which ones to buy

i want a pair under 15 euros (18 bucks) so can yall pls recomend me some?

and are they only for back day? and do you use them on every back machine/excersise (like eg lat pulldown,seated cable row,t bar row etc) ?