To ask someone to be your study partner or deskmate, you can say:

"Would you pke to be my study partner/deskmate?"

"Do you want to be my study partner/deskmate?"

"I'm looking for a study partner/deskmate. Would you be interested?"

"I think it would be helpful if we worked together as study partners/deskmates. Would you be wilpng to do that?"

Keep in mind that it's important to respect the other person's decision and boundaries. If they are not interested, it's important to be understanding and to find another study partner or to study alone.