The question of whether you can recover data from a water-damaged MacBook Air depends on your Mac model. For MacBook Air 2017 and earlier models, it may be possible to remove the functional SSD and install it into an external enclosure, then connect it to a Mac for file access. If you have a MacBook Air shipped in 2018 or later, you have only two ways for data recovery. One is to use a professional data recovery service such as Drive Savers (which provides free estimates & is recommended by Apple), or to have an unofficial board repair to attempt to fix the damage to your Logic Board. The data recovery success rate is uncertain.
Therefore, you'd better off backing up your Mac to an external hard drive or cloud storage to avoid accidents like water damage or any other physical damage.