B.T. booster.
 

Got bt to sort my poor reception,which i am now pleased with.
But when i use my firestick in bedroom get "fair" connection from router, which is a little troublesome anyone recommend a GOOD booster to purchase. Thanks.

Are you using a BT Smarthub?

If not, I would upgrade to that before trying anything else. It has the strongest WiFi performance of any ISP router.

I have a BT Smarthub and it is good.

My old house has thick cob walls and I have installed a booster in the bedroom at the far end. It works very well.

I went for the Netgear AC1200 Dual Band Extender, like this one here

I have a Smarthub. I also had trouble when i upgraded my sky,they had to put in booster to get reception to my wireless 2nd box in bedroom.