Laptop loading everything slowly and fan making loud noises

Imogen, you want to make sure that you check your computer for Viruses and Malware first. Use programs of your choice, I prefer Avast and Malware Bytes. If your machine is clean, you want to check and see what is going on in the background. I use "What's my computer doing" to check on that. See what it is loading when it starts up. MSConfig should show you that. also, check the answer by "Gary" on here, makes a lot of good points on what to do. Once you are satisfied that you eliminated all unnecessary processes, check your hardware. It is possible that your fan is either dirty, or just worn out. you also want to make sure that you have good airflow through the vents. If you let us know which model Samsung you have, we might be able to help you further.