Hi @pranavj619
Assuming New Screen name is 'Screen1', please use the following formula in onSelect function of gallery:
Navigate(Screen1,Transition.None, {varRecordID:Gallery1.Selected.ID});
assuming Gallery1 is the name of gallery.
Create a new Screen with name 'Screen1' and add a form control on it. Modify the form control 'Default Mode' property to New.
In the item property of edit form add the following formula:
LookUp(SPLisName,ID= varRecordID)
Add the required fields in the forms as shown below:

Please let me know if you face any problems.
Thanks
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