there is no problem if the temp is going 80 deg C. no need to open laptop or anything. If ur system starts shutting down automatically or starting to hang then only u should open and change the thermal paste.
Yes if it is get up to 80C+ than you have a problem, does your case have enough airflow is it big enough to fix everything in it nice and neat if you have that than i suggest to buy some more 120mm fans.
when im gaming its over 80c degrees crazy and when im not gaming its round 40-50c so is it normal that i get 80 c degrees?
laptops are know for bad cooling and while your gpu is hitting 80*c its not the end of the world. try blowing out all the cooling vents and or if you think you can do it, open the laptop and replace the thermal paste on the gpu..... if you go that far might as well replace the paste on the cpu as well. make sure everything I clean and blown out and put it back together.
You could also look into a cooling pad for it as well.
that kind of temperature is norm for high end gpu. not to mention the cooling on laptops are more limited as compared to desktop pc. just make sure all the heat exhaust have enough clearance to dump all the heat.
i always gaming on my couch or shall i game on my desk ?
gaming from the couch is fine just grab a cutting board or a sidle panel from an old case to give the laptop something hard to sit on so it gets airflow under it.
there is no problem if the temp is going 80 deg C. no need to open laptop or anything. If ur system starts shutting down automatically or starting to hang then only u should open and change the thermal paste.