Hi @Surendran_R ,
When we use power page site on smartphone and have to scroll left to navigate EDIT record, you can make the first column clickable and can navigate to the Edit the record,
Step 1: Navigate to the list in Portal Management.
Step 2: In general tab look for "web page details view".
Step 3: Update the page where the form is present for the respective record to edit the record,

Save the list record, Sync the Portal site,

As you can see the account name is now clickable and navigate to edit form of the record to update the details of the same.
Also, in case if You want that the entire row should be Clickable then you can refer the below blog,
https://oliverrodrigues365.com/2021/06/30/power-apps-portals-entity-list-making-the-entire-row-clickable/
If this answer helps, please mark it as an Accepted Solution so it would help others to find the solution.
Thanks!
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