I want to start by pointing out that we know very little about Germanic beliefs. They are entirely rooted in very, very limited inscriptions (that basically just cover some names), Tacitus referencing a Germanic deity Nerthus, and the Prose Edda, and the Poetic Edda.

The Prose Edda was likely compiled by Snorri Sturluson in the early 13^th century about 300 years after Iceland had become Christian and was never really intended to be used to teach about the Norse gods, but rather to teach poets about alliterative verse. There are only seven surviving copies - each is incomplete, and they all have differences. The Poetic Edda is a collection of older poems, and most of our copies come from a single source (the Codex Regius) which itself has variations. The Codex Regius itself was likely compiled in the late 13^th century.

Another thing to note is that most 'pagan' belief systems weren't monolithic or structured like you'd think of when you think of a modern religion. Practices and beliefs could and would vary from village to village, and sometimes within villages. There were generally strong commonalities within a cultural region, though - someone from Rome, for instances, would have completely recognized what was practiced in Tibur, though they would have noticed differences. If they'd gone to somewhere like the Samnite city of Maloeis (Maleventum/Beneventum), it would have still been largely recognizable but differences would have started to become apparent. This is no different from any other group such as the Greeks or the Germanic Tribes.

That being said, all of the Germanic gods, including the Norse, derive from the early Common Germanic (often called Proto-Germanic) pantheon. Linguistically, it first divided around the 3^rd century with the East Germanic languages (Gothic and Vandalic) splitting off, and then rhe remaining Late Germanic dialects splitting onto North and West Germanic. Culturally and in terms of religion, differences would have followed these groups.

When you search for 'Germanic gods', the ones that we have that are best attested are the Norse gods (which were the deities of the Norse, the North Germanic peoples), which were very closely related to those of the East and West Germanic peoples, though they were not entirely the same. We have very, very little information regarding West Germanic beliefs, so any searches you come up with will almost always be in reference to Norse beliefs as those are the best attested (if not entirely reliably so).

Are they the same? In a manner of speaking, yes, and in another manner of speaking, no. Is the English word "house" the same as the German word "Haus"? They're cognates, derive from a common source (Common West Germanic *hus, Common Germanic *husa), mean the same thing... but they're words from different languages now. There would have been differences even between different Norse groups regarding their beliefs and practices, let alone between Norse and West Germanic (such as Saxon) beliefs and practices, but they would have been largely familiar and similar. You are, however, looking at nearly a millennium of accrued differences between them.

As to what the actual Germanic 'religion' was/would have been? We honestly don't know - we can only extrapolate and make educated guesses. As said at the start, almost all of our knowledge is based on fragments that primarily are just names, and the Eddas which were compiled hundreds of years after Christianization and only really cover late Norse beliefs. We can try to take some of our knowledge of Greek or Italic belief systems and map it to them, as they all derive in the end from a common Indo-European religion, but that really doesn't net you much.