If your Wi Fi router's reach does not extend all over the house - does it help to install a booster ? Can we do it ourselves and how can we do it ? Or should just forget about it and use the laptop only in the rooms where it works.
Booster should help in sending the signals all over the house. You have to check whether your Wi-Fi router will be supported by boosters or not. There is no harm in trying. It is the only way one can learn. So give it a try before using your Laptop only in those rooms where the signals are available.
before investing money check the location of your router, if it is stuffed into a corner of the house it might be good to think of moving it to more of a central place in your house.
you can get signal boosters but i am not sure how effective they are, they must work ok.
also have you tried another device connecting to it? it might not be the router but the device you are trying to connect such as your laptop wireless connection is very weak.
You can definitely install it yourself if you were able to configure your router. You should try Dave's suggestion, it can make a big difference at times.