Tolkien was, by profession, a philologist. This is an academic that studies the intersection between literary criticism, history and linguistics, with a particular eye to the developing cultural history of texts. As such, he had an extremely deep understanding of the etymology of English words and how that history can impact the reader in unconscious ways.
Take, for example, place names in the Shire. They are archetypically English: even the word "shire" is the generic English name for a county. The "farthings" are derived from the old English feorðing, meaning "quarter", and the name survives in many English villages today. There are further examples. Aside from the Baggins family, many hobbits in the shire bear similarly English names like Sam and Pippin.
The action then moves to Bree. Bree is not an English name: it is a Welsh word, meaning "Hill". The characters the hobbits meet there also bear Welsh names like Archet, which derives from "ar chet" meaning "the wood" or Combe which is from the Welsh "cwm", for "valley".
This is deliberate. Tolkien believed that by these subtle markers of language he was communicating something important to the reader. Namely that the hobbits start out somewhere familiar and safe and gradually move away from that familiarity into danger. Bree is Wales: foreign, but a known quantity. In Rohan, the place and character names are derived from Old English, conjuring Britain's distant past. Gondor is the ultimate alien place, where people and places are named in a wholly invented language with no linguistic connection to English at all.
This may be the root of some of the problems you're experiencing. If you're not a native speaker, a lot of these subtle linguistic allusions may be lost on you, making the tale as a whole harder to understand and appreciate. Yes, Tolkien was purposely making his writings look ancient for this kind of story. He wanted to recreate the lost mythology of England and to echo the mythic language of other European mythic epics. He had the professional knowledge to do it, and employed that knowledge in very detailed, specific ways that may be impenetrable to non-native speakers.
References:
- JRR Tolkien: Author of the Century by Tom Shippey