There is lots happening online with ukulele groups having stumalongs, online choirs and lessons galore. I will add a few of them on here with links as I come across them.
Gareth Malones National ChoirParagraph
Ukulele Wednesday they have a Facebook page Self-Isolating Strummers / Pandemic Pluckers they meet online every night of the week using zoom
if you know of any more let me know and I will add them here