Learn French: J'achète un panier dans ce rayon. - I am buying a basket in this aisle.

Acheter (to buy) is a stem-changing verb. In the present tense, the first e changes to an è for the je, tu, il/elle/on, and ils/elles forms (like j'achète). This happens because those forms have silent endings, and the accent changes the pronunciation so the word flows better. The nous and vous forms keep the plain e because their endings are pronounced (for example, nous achetons).

The translation says "I am buying," but doesn't j'achète mean "I buy"?

It means both! French does not have a separate present continuous tense (an "am doing" form) like English does. The simple present tense j'achète can translate to "I buy" or "I am buying" depending on the context.

Why is it ce rayon instead of cet or cette?

Ce is the demonstrative adjective (meaning "this" or "that") used for masculine singular nouns that start with a consonant, like rayon. You use cet for masculine nouns starting with a vowel sound, and cette for all feminine singular nouns.

Does rayon really mean "aisle"? I thought it meant a ray or a beam.