Yes, you CAN legally use copyrighted music in YouTube videos BUT you need to understand how YouTube's copyright system works.

Can you get copyrighted for instrumentals on youTube?

" Are we allowed to add the artists songs as long as we give credit " : No, not without permission from owner of the songs. Otherwise, they could find your channel and strike you with copyright infringement.

Do instrumentals get copyrighted?

Generally, you'll need to purchase a copyright license to use an instrumental legally. The only exceptions are where you're using an extract of the music for education purposes or the instrumental is so old it has fallen into the public domain.