htaccess internal masked redirect - .htaccess

Question

I've been searching for hours on how to get say www.xyz.com/payroll to load the contents of www.xyz.com/react while still displaying www.xyz.com/payroll in the address bar
all i have so far is a basic redirect which changes the URL in the address bar to xyz.com/react:
RewriteEngine On
RewriteRule ^payroll/?$ /react [L]
`# BEGIN W3TC Page Cache core
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteCond %{HTTPS} =on
RewriteRule .* - [E=W3TC_SSL:_ssl]
RewriteCond %{SERVER_PORT} =443
RewriteRule .* - [E=W3TC_SSL:_ssl]
RewriteCond %{HTTP:X-Forwarded-Proto} =https [NC]
RewriteRule .* - [E=W3TC_SSL:_ssl]
RewriteCond %{HTTP:Accept-Encoding} gzip
RewriteRule .* - [E=W3TC_ENC:_gzip]
RewriteCond %{HTTP_COOKIE} w3tc_preview [NC]
RewriteRule .* - [E=W3TC_PREVIEW:_preview]
RewriteCond %{REQUEST_METHOD} !=POST
RewriteCond %{QUERY_STRING} =""
RewriteCond %{HTTP_COOKIE} !(comment_author|wp\-postpass|w3tc_logged_out|wordpress_logged_in|wptouch_switch_toggle) [NC]
RewriteCond %{REQUEST_URI} \/$
RewriteCond "%{DOCUMENT_ROOT}/wp-content/cache/page_enhanced/%{HTTP_HOST}/%{REQUEST_URI}/_index%{ENV:W3TC_SSL}%{ENV:W3TC_PREVIEW}.html%{ENV:W3TC_ENC}" -f
RewriteRule .* "/wp-content/cache/page_enhanced/%{HTTP_HOST}/%{REQUEST_URI}/_index%{ENV:W3TC_SSL}%{ENV:W3TC_PREVIEW}.html%{ENV:W3TC_ENC}" [L]
</IfModule>
# END W3TC Page Cache core
# BEGIN WordPress
# The directives (lines) between `BEGIN WordPress` and `END WordPress` are
# dynamically generated, and should only be modified via WordPress filters.
# Any changes to the directives between these markers will be overwritten.
<IfModule mod_rewrite.c>
RewriteEngine On
RewriteBase /
RewriteRule ^index\.php$ - [L]
RewriteCond %{REQUEST_FILENAME} !-f
RewriteCond %{REQUEST_FILENAME} !-d
RewriteRule . /index.php [L]
</IfModule>
# END WordPress
# BEGIN (mt) controlled settings
AddHandler php-latest .php
# END (mt) controlled settings
`
following code in htaccess already: