The most common practice for Jewish families is to spend the first night of Seder at a home gathering with family and friends. Some synagogues won’t even have Friday night Shabbat services this week because Shabbat coincides with First Night Seder this year. Typically people spend the second night Seder at a Community Seder, often at a synagogue. Therefore, second night Seders are much easier to come by.
If you belong to a synagogue the rabbi typically does “matches” for first Seder. So if you’re a member, call your rabbi to see if there is someone with an extra seat or two at their table.