Ukulaliens is awesome!! Very well organised and a wide range of styles of popular music. This YouTube channel contains a large number of well-produced Ukulele play-along videos of well-known popular songs. Many of the play-along videos have a matching tutorial video which works through the chord formation and strum patterns needed. The link to the tutorial is in the comments under the playalong so this makes it super easy to find!

Visit their website at https://www.ukulele.wales/

This is a channel created by Kevin Way who is the Ukulele teacher at Fredonia Middle School. He has created some excellent play along video files which are clear and easy to follow. They range in difficulty depending on the chords required to play the song.