Internet problems

back late last year my homes internet has been basically unusable and i don't know why, the router and modem lights are as they were when the internet worked well, theres no internet outages near me, and i havent had a problem like this ever. ive been using my mobile hotspot for everything including lending it to my brothers, its really miserable and i have no clue what to do. (yes ive reset the router using the button on the back)