Hi @G0Springs ,
Do you want to edit PDF in Flow with the parameters passed by Power Apps?
I am afraid that there is no directly way to achieve this in Power Apps and Power Automate currently.
Is it necessary to edit an existing PDF instead of creating it from scratch?
I have made a test for your reference.
I wrote HTML in Power Apps and converted it to PDF in Flow.
1. Create a flow.

2. Create a App.
3. Add a HtmlText Control and apply the following formula on its HtmlText property as:
"<br><strong> Title: </strong>"&
"<br><table width='100%' border='1' cellpadding='5' style='border:1px solid black; border-collapse:collapse'>" &
"<tr style='background-color:#efefef'>
<th> fieldname</th> <th> fieldname </th> <th> fieldname </th><th> fieldname </th><th> fieldname </th>
</tr>"&
Concat(yourdatasourcename,"<tr>
<td>" & fieldname(.Value) & " </td>
<td>" & fieldname(.Value) & " </td>
<td>" & fieldname(.Value) & " </td>
<td>" & fieldname(.Value)& " </td>
<td>" & fieldname(.Value) & " </td>
</tr>")&
"</table><br>"&
"<strong> MapTrackTest: </strong>"&
"<br><table width='100%' border='1' cellpadding='5' style='border:1px solid black; border-collapse:collapse'>" &
"<tr style='background-color:#efefef'>
<th>Title</th> <th> MapLabel </th> <th> MapLongitude </th><th> MapLatitude </th><th> MapColor </th>
</tr>"&
Concat(MapTrackTest,"<tr>
<td>" & Title & " </td>
<td>" & MapLabel & " </td>
<td>" & MapLongitude & " </td>
<td>" & MapLatitude& " </td>
<td>" & MapColor & " </td>
</tr>")&
"</table>"

4. Add a Button Control and apply the following formula on its OnSelect property as:
YourFlowname.Run(HtmlText1.HtmlText)
Result Screenshots:


Best Regards,
Charlie Choi