How to make computer use internet only with proxy SQUID PFSENSE

See the Squid documentation for the cache_peer directive. For a proxy on parentcache.foo.com:8080, you could use something like:

cache_peer parentcache.foo.com parent 8080 0 no-query default login=user:password
acl all src 0.0.0.0/0 
never_direct allow all

SO in PF you have to do the following:

int_if="fxp0"
ext_if="em0"

rdr on $int_if inet proto tcp from any to any port www -> 127.0.0.1 port 3128

pass in on $int_if inet proto tcp from any to 127.0.0.1 port 3128 keep state
pass out on $ext_if inet proto tcp from any to any port www keep state

Be sure that your SQUID has the transparent module when you compiled it, or the package is transparent enabled you are using.