This is vague and contradictory. Please read "How do I post a question effectively?" and "SSCCE". Most of what follows is pure guesswork in terms of what you actually need.

Use of non-interpolating quotes would normally suffice:

$ perl -Mstrict -Mwarnings -E 'my ($u, $p) = (q{W$X}, q{Y@Z}); say for
+ $u, $p'
W$X
Y@Z
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Use of interpolating quotes would normally cause problems:

$ perl -Mstrict -Mwarnings -E 'my ($u, $p) = (qq{W$X}, qq{Y@Z}); say f
+or $u, $p'
Possible unintended interpolation of @Z in string at -e line 1.
Global symbol "$X" requires explicit package name (did you forget to d
+eclare "my $X"?) at -e line 1.
Global symbol "@Z" requires explicit package name (did you forget to d
+eclare "my @Z"?) at -e line 1.
Execution of -e aborted due to compilation errors.
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See also quotemeta.

What you wrote about the "URI::escape" and (later) "uri_escape" doesn't make much sense. URI has neither an escape() function nor a uri_escape() function; URI::Escape has the latter. Even my best guess at fixing typos doesn't help:

$ perl -Mstrict -Mwarnings -E 'use URI::Escape; my ($u, $p) = (q{W$X},
+ q{Y@Z}); say for uri_escape($u), uri_escape($p)'
W%24X
Y%40Z
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We'll need some clarification on what you're actually doing here.