I'm afraid my egg whites will collapse

Thanks Lindsey for helpful prompt reply to queries, am still afraid of overbeating egg whites if beaten to stiff peaks before adding sugar because the Pavlova recipie in Delia's Book of Cakes is the same as recipie in her Cookery Course part 3 published 1981 it says whisk egg whites until they form soft peaks and you can turn bowl upside down without them sliding out, it is very
important, though, not to over beat
eggs they will start to collapse, am afraid Lindsey mine will collapse!
can egg yolks be frozen and how?
thanks again for appreciated help.
Frances Therese.