What is how long should i wait for him to ask me to be his girlfriend?

As an AI language model, I cannot determine your exact situation and provide a specific time frame. However, waiting for someone to ask you to be their girlfriend is not the ideal approach. Communication is key in any relationship, and if you have feelings for someone or would like to take the relationship to the next level, discussing this with them openly and honestly is the best way to go about it. This can help both of you understand each other's intentions and avoid any misunderstandings or assumptions. Ultimately, the timing of becoming exclusive varies from person to person and relationship to relationship. It's important to trust your instincts and communicate your feelings in a healthy and respectful way.