Is it possible to connect online through multiple WiFi on my laptop?

No, You can only connect to a single Wi-Fi connection at a time. There is no trick to combine Multiple Wi-Fi connections and use them as a single connection.

However there are several tricks on the web which assures you that you can use multiple Wi-Fi as a single one but I do not approve of these methods. The thing is that even if you somehow manage to use multiple Wi-Fi's then your computer will still prefer to use the connection with the fastest speed. So, it will still use a single Wi-Fi out of several available ones.

New version of connectify pro have the ability to connect the multiple wifi at a time and speedify is also the application which provide the similer feature apart from this user can also connect the speed of dongle and LAN cable too

I guess there is no such way to use multiple Wi-Fi at a same time. But you can still find many fake or non-working ways to do so. So please don't believe them because they can cause some damage to your OS. But if you find any of the tricks available on famous and trusted websites then you can try them but at your own risk.

Yes, it is possible to combile different Wi-Fi networks and use them on a single single laptop or PC. An app namely Speedify and do so. It was previously known as Connectify Dispatch.

With Speedify, you cna combine speed of different networks Wi-Fi, 3G/4G, DSL, Broadband etc. to make a single super fast net connection on a PC.

Here is How it Works :
1. Firstly, turn on the Wi-Fi of your laptop and connect it to a nearby Hotspot.

2. Then, tether you smartphone 3G/4G network to you PC.

3. Now, open the Speedify app on your PC and combine both connections to make a single net connection.