Hi there! I'm assuming you are asking about conjugating regular (versus irregular) -AR verbs in the present tense, so that's how I'll answer this question.
To conjugate a verb, simply remove the -AR from the end of the infinitive. Then, add the appropriate ending that corresponds to the subject. Let's use the verb CANTAR as an example.
-AR Verb Endings: -o, -as, -a, -amos, -áis, -an
Él, Ella, Usted canta
Ellos, Ellas, Ustedes cantan
Does that make sense? Please let me know if you have any questions or need further clarification.