Which god should I worship?

I am unsure which god to worship and I am relatively new to Hellenismos. I really like poseidon but I'm not a fisherman or a boat captain or anything. Anyone have any tips or anything?

All of the Gods are worshipped; you do not "choose one".

However, not every deity is worshipped on every occasion or instance. For example, household worship is nearly always centered on Ἑστία/Vesta and the Domestic Jove [Grk: Ζεύς-Μειλίχιος]. Heracles, Apollo-Thyraeus, Enodia, and Fortune are also commonly worshipped at the home for the purposes of seeking protection from potentially harmful forces outside the home (in the case of Heracles, Thyraeus, and Enodia), and Fortune for the sake of the overall prosperity and well-being of a household (often as a consort of Μειλίχιος).

Outside of this, the gods worshipped in any particular time depend on many factors: lifestyle/job, location, family, aspirations, season, day, and even hour.

Gods are also far from one-dimensional. Poseidōn is indeed the god of the seas, but is also a god of horses, business, metalworking, earthquakes, the lower sky, and storms, in terms of the physical world, and religiously, is the god of the Progression of the Soul. Pisces/Ichthys (late February-late March) is the month sacred to Poseidōn, and is numerically associated with the number 6 (and so, would be associated with times with '6' as their characteristic (i.e. Saturdays, the sixth hour of the day/night, etc.).

All of the Gods are quite sophisticated. I would encourage you strongly to read through some of the overviews in this section: Dodecatheon, as well as the pages compiled at Theoi.com

It would also be beneficial to read through the 'Stickies' posted at the top of each forum, especially the ones here in the Beginners section.

Best, and welcome to the forum.