Make a quick siyum on:
If you are a firstborn, or if you are a father of a firstborn son under barmitzvah, you should either
fast or attend a siyum on Erev Pesach.
This year, most communities are in lockdown due to the novel coronavirus (COVID-19) pandemic.
This makes attending a siyum in-person almost impossible.
Therefore, based on authoritative halachic advice:
It is preferable for you to complete a Masechta of Gemoro yourself, between now and Erev Pesach.
The shortest Masechta is Tamid, with eight blatt (double-sided pages).
It is reproduced here with English translation
The next best preference is to learn Pirkei Avos properly (i.e. with a full commentary, whether in Hebrew or English).
This is found in most Siddurim after Shabbos Mincha.
The next preference is to hear a Siyum by phone or video.
Regardless, you should have special food present to commemorate the Siyum.