Creating cards

Does anyone know how to create small folded NOTE cards in CANVA?

My neurodivergent brain is failing me.

I want to make 3.5 x 5 and 4 x 6 FOLDED.

I am confused as to how I know I have the right size (i have made the wrong size before)

Do I choose a flat 7 x 5 template? and fold them. But then the envelopes will be too large. Any help is appreciated.