In the example code:
- Donate is the current button text. You need to change it to your current button text.
- new text is new button text. You can change it to new text
- Google.com is an example URL. You can change it to the URL that you want
One Page
#1. Enter this code in the Page Header Code Injection and click Save
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).ready(function(){
$("a.btn").html(function() {
return $(this).html().replace("Donate", "new text");
});
$("a.btn").attr('href','https://google.com');
});
</script>

#2. You will have a result like this

Cart Page
#1. Add this code to Code Injection > Footer and click Save
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).ready(function(){
$("body#cart a.btn").html(function() {
return $(this).html().replace("Donate", "new text");
});
$("body#cart a.btn").attr('href','https://google.com');
});
</script>

#2. You will have a result like this

Paywall Page
#1. Add this code to Code Injection > Footer and click Save
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.7.0/jquery.min.js"></script>
<script>
$(document).ready(function(){
$('#sqs-paywall-page-root').closest('body').addClass('paywall-body');
$("body.paywall-body a.btn").html(function() {
return $(this).html().replace("Donate", "new text");
});
$("body.paywall-body a.btn").attr('href','https://google.com');
});
</script>

#2. and result like this.
