Once you have sent a proposal to a buyer, you can check to see if the buyer has viewed it and also if the listing is still active or closed.
To check the status of a proposal:
1. Click on the main drop-down menu (circle in the top right-hand corner with your profile image)
2. Click SELLER
3. Then click on MY PROPOSALS
From here you will see all the projects you have submitted to as well as their status and if the buyer has viewed your proposal or not.
Directly to the right of MY PROPOSALS you will see how many proposals you have remaining for the current month (for more info check out this article on how many proposals you can send per month).