Learn French: Il y a une belle lampe sur la table. - There is a beautiful lamp on the table.

Most adjectives in French go after the noun, but short, common adjectives describing Beauty, Age, Number, Goodness, and Size (often called the BANGS rule) go before it. Since belle describes beauty, it goes right before lampe.

Why use belle here instead of beau?

The noun lampe is feminine, so the adjective needs to match it. beau is used for masculine nouns, while belle is the feminine form.

Since we are learning about chez, could I say chez la table to mean at the table?

No, chez means at the home or workplace of, and it is strictly used with people or professions (like chez le médecin). For inanimate objects like a table, you must use regular prepositions like sur (on) or à (at/to).

Why is the expression Il y a used here for there is?

Il y a is the standard French expression for there is or there are. Even though it literally translates to it (il) there (y) has (a), it acts as a fixed phrase that you shouldn't try to translate word-for-word.