What can I use to cover up popcorn ceiling?

https://www.hometalk.com/categories/remodeling-renovating/ceiling/popcorn-ceilings

You could try Wall liner. It’s sort of like a super thick paintable wall paper. It’s great over paneling but I’m not sure about the lumpy texture of a popcorn ceiling.

Thin sheets of plywood could do the trick as well.

The big concer is if your ceilings contain asbestos.

Artex (texture coating)

Until the mid-1980s, the Artex coating was made with white asbestos to strengthen it. Therefore old Artex manufactured by Artex Ltd. will contain asbestos while Artex coatings applied after 2000 may or may not contain asbestos. It is also worth noting that the texture is only harmful when in a powder form, i.e., being sanded, and poses no risk while it is undisturbed (without drilling holes or more substantial practices) on ceilings or walls and covered with emulsion paint.

Removing even more modern non-asbestos coatings can expose the operator to hazardous dust particles. Older coatings, containing asbestos, pose a particularly serious hazard. Inhaling microscopic asbestos fibers can cause asbestosis, a fibrosing lung disease; pleural mesothelioma, a cancer of the lining (pleura) of the lung; and peritoneal mesothelioma, a cancer of the lining (peritoneum) of the abdomen. Professional expertise to identify the presence of asbestos is recommended.

Hope that helps

😊

You can install 1/4" drywall over it, but its a lot of work too.

Wall liner would not work on a popcorn ceiling.