Entity choice affects liability exposure, tax treatment, governance flexibility and the ability to raise capital. Some of those are easy to change later and some are not.
Limited liability company. Default choice for closely held operating businesses. Pass-through taxation by default with the ability to elect corporate treatment; near-total governance flexibility through the operating agreement; and simple maintenance. Drawbacks appear when institutional investors are involved, since venture funds generally require a corporation.
Corporation. Two tax regimes. Subchapter C means entity-level tax and a second tax on distributions, with the benefit of retained earnings at corporate rates and access to qualified small business stock treatment for eligible holders. Subchapter S is pass-through, with strict eligibility limits — one class of stock, limits on the number and type of shareholders.
Partnership forms. General partnerships expose partners personally; limited partnerships protect limited partners who do not participate in control; limited liability partnerships are used by professional firms.
What is hard to reverse. Choosing a corporation and later converting can be straightforward; converting a corporation with appreciated assets to an LLC is usually a taxable event. That asymmetry argues for careful analysis at formation.
Jurisdiction of organisation is a separate question governed by governance law, franchise taxes and investor expectations.