Fan on +4000 rpm on startup and always.

Hi everyone
I hope I can get some help from you.
I bought an Asus laptop X540ubr in 2019. At the beginning of 2022, the fan started running on full speed since boot combined with me having to click the power button multiple times to power on my laptop. I took the laptop to an expert shop. They fixed it and said they only did some cleaning for something that was caused by humidity. They told me Also that my hdd was damaged and they recommended that I change it and I did, I got a 512GB ssd and the laptop worked perfectly for two months. Now, since more than 5 month I have the same problem with the fan. I opened the laptop, cleaned the fan and ventilation area (which was clean), I changed the thermal paste but thst didn't resolve the fan problem or the power on PROBLEM. In addition to that, my laptop freezes sometimes and gives the blue death screen, critical process died then restarts to ask me to enter media device. Then I turn it off and on and it works (with the fan still on high speed) and the power on problem.
I don't know if there is something wrong with my ssd although I tried chdsk and all seem to be well.
I tried downgrading my bios and re upgrading it. Nothing worked.
I also tried to use it on battery without ac or on AC without better without any luck.
I'd be grateful for any ideas you might have to help me out.
Thank you in advance.