This way Sara: Every painter and musician is welcome at court. Notice that painter and musician is "singular" as Charlie shows. Now watch as we switch to the "plural". All painters and musicians are welcome at court. or All the painters and musicians are welcome at court. or Only a select few of the best painters and musicians are welcome at court. Even apprentice painters and musicians are welcome at court. Only the very best students and craftsmen are invited to the competition. Only one very gifted student, along with an abundance of athletes, were invited to compete. All singers and songwriters are welcome to appear on the TV show.

"Every painter or musician is welcome at court" would be correct. Adding the s at the end of painter and musician is redundant since you already said "every". Besides that, it looks good! :)

You can try to write note book entry ok .It's easy to correct your mistakes.

Every painter or musicians are welcome at court.

every painter or all painters. every is used with the singular