Through the help of folks on this forum, I was able to get my multi-select checkbox from my SP list to my Edit Form in Power Apps using a Gallery.

The checkboxes appear to work but I am missing a step. When I update/save the record the checkbox selections are not being written to the SP list. Maybe something about On Select or the Update. Here are setting on the checkbox control I think play a part:
Default = false
OnCheck = Collect(Colreport, ThisItem.Value)
OnSelect = false
OnUncheck = RemoveIf(Colreport, Value=ThisItem.Value)
Reset = VarClearCheckbox
Text = ThisItem.Value
How can I get the selections to write to the SP list?