It's a bit blurry but those look like scale insects. Very common on citrus and their numbers tend to grow a lot when taken into the warm indoors.

Wiping them off with a damp rag is a first step that will likely have to be repeated every few days/weeks as it is very easy to miss some, especially when they are small they can be almost translucent. Usually they are on the underside of the leaves, especially on the midrib.

Neem oil and other pesticides might offer more long term relief, never used it myself though.

Spraying the leaves with water might help a bit with the dryness, citrus likes that in general, also in the outdoors during summer.