I have found on the Czech web some advice

how to wear veil(mask) together with glasses

Ivana Urválková, director of the International Association of opticians and optometrists, advised how to prevent glasses from fogging.
Wearing drapes (veil, mask...) brings inconvenience to many people with glasses in the form of fogging of glasses. As soon as a person puts on a mask and glasses, the glasses immediately begin to foggle. 
As a person breathes in the veil, the upper part gets warm exhaled air under the glasses, and thus they become foggy. A problem now solved daily by tens of thousands of people. Therefore, it is important how we put the protective device on and how we adjust it on the face. An ordinary homemade mask is advised by experts to tie as much as possible to the eyes. 
To prevent fogging wash  glasses daily in a solution of lukewarm water and dishwashing detergent. After that, let the glass dry and, most importantly, do not polish. Experts do not recommend even using disinfection on glasses, it can damage not only glass, but also plastic. 
You can also consider maybe  the easiest possibility for some of us - to replace glasses with disposable contact lenses, at least for the necessary time.

                                Enough already, disappear, coronavirus !!

                                                                        Wishing you good health

                                                                                                    Margaret