Oleksandr The speed is limited by your network card (WIFI). You can connect your laptop via LAN and do a speed test to check the speed. Also you can replace / exchange your network card, so that you then have the full speed.
Personally, if you are working from home, I always recommend connecting your computer via LAN. It is enough for a neighbor to turn on a strong WIFI to spoil your WIFI experience.
As for the subscription, we have 100 mbit on the smallest subscription. Even with this, you would have a loss of 46 mbit.