@JillLJ
Step 1 : https://make.powerapps.com
Step 2 : select solutions from the left NavBar , And select "New Solution" on your top left and fill all the details
Step 3 : Now, select the solution You've created - On the top left select "NEW" - "APP" - "CANVAS APP" (Acc to your preference) and fill the details like app name etc.
Please note : once the app is open you must publish it atleast once for it to be saved, or you will have to redo the app.
Let me know if you need any further help
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