Can I connect my Android device to a laptop via WiFi to use file sharing?
Plenty of solutions available here. Depending on which device you want to work (i.e. using your Android device to push things to/pull things from your laptop, or working on your laptop and accessing the Android device), your choices may differ, though:

ES File Explorer is a file manager app for Android which also can access remote resources via WiFi. Amongst others, it supports CIFS (aka "Windows Shares") and FTP.


ES File Explorer (Source: Google Play)

AirDroid is an app running on Android, and offering access via web browser. So you can work from your laptop and access your Android device via a web interface.


Airdroid (source: Google Play)

Both variants require your Android device and your laptop being in the same network (well, there are ways around this restriction — but this is how it definitly works). Using the same WiFi access point for both should guarantee that, for example.