If you subscribe to HIAS Computing Friendly then the latest edition is full of teachers experiences using Google Classroom, Seesaw and Microsoft 360. These will help you make an informed choice.
In Hampshire Google Classroom & Seesaw were the platforms chosen by the vast majority of primary schools during lock-down.
If you would like help and online training get in touch firstname.lastname@example.org
I used Google Classroom extensively for both my schools during lock-down and training feedback from other schools has been excellent.