Learn Turkish: Ben kahve seviyorum.

In this lesson, we are learning personal subject suffixes. For the pronoun ben (I), the suffix after the -yor tense marker is always -um. The verb breaks down into sev (like/love) + -iyor (continuous tense) + -um (I).

Do I have to say ben if the verb already ends in -um?

No, you can simply say Kahve seviyorum. Turkish often drops subject pronouns because the verb ending tells you exactly who is doing the action. Adding ben here just puts a little extra emphasis on the fact that you are the one who likes it.

Why does Turkish use the -yor (present continuous) tense here? We do not say 'I am liking coffee' in English.

Turkish uses the -Iyor tense for many feelings, states, and habits where English uses the simple present tense. Verbs about emotions, like sevmek (to like/love), almost always take the -yor ending even when talking about a permanent feeling.

Why is there no ending on the word kahve?

Because you are talking about coffee in general. In Turkish, when you make a general statement about liking or disliking a whole category of things, you leave the noun in its plain, dictionary form without any extra endings.