19 year old non-practicing catholic wanted to attend synagogue for the first time?

I am a 19 year old non- practicing catholic. I've always been interested in Judaism and have wanted to experience temple for awhile now. I plan on attending the synagogue a block from my house tomorrow & have no idea what to expect or prepare for. Am I aloud to be there? Ithe only advice I've been given so far was to wear a shawl over my head..... Any help/suggestions?

I think it would be interesting for you. You can see what your religion is the fulfillment of.

I'd ask one of the rabbis before you go.

there is a story about a man who asked what to do regarding visiting a synagogue.
a Jewish comedian suggested that he sit outside and eat and orange,
"then watch the juice [ Jews ]run out."

Tomorrow is Sunday, today was the Sabbath so I doubt there will be services tomorrow although there could be classes. Call the synagogue and talk with the rabbi and tell him you are interested in visiting. Leave the shawl at home, most Conservative and Reform women do not cover their heads to begin with and even if it is an Orthodox synagogue a woman who is not Jewish would not be expected to cover her head.

A lot of this depends on what type of synagogue is a block from your house.

If it is an Orthodox or Chabad Synagogue, then you should plan to attend Sabbath morning services. Where clothing that covers your upper arms and legs at least to your knees. Don't show cleavage. Chabad services usually begin after 9AM. Other Orthodox services likely begin between 8:30 and 9AM and run for about 2 1/2 hours.

If it is a non-Orthodox Synagogue, plan to go to the Friday night services.

In either case, don't even think of wearing a shawl over your head. Check when the service you're planning to attend begins.

Good luck.