2019 was my first time filing federal tax; it was by mail and it hasn't been processed. Can I go ahead and file for 2020 electronically?

Hi,

I moved to the country recently, and for my 2019 Federal Tax Return my wife needed to apply for an ITIN, so we had to file by mail. This was in July.

She has her ITIN now (it finally arrived in late October), but the tax return hasn't been processed yet.

Can we go ahead and file for 2020? Or do we need to wait until we get 2019 cleared (or is it just a better idea)?