Dell G3 15 hdd always run 100% at starting windows

Now I faced with problem about HDD that run 100% when windows start. this problem make me wait around 5-10 minute before run any program. I did disable some start up program and checked hardware. It’s showed that HDD is fine, no problem found. Now I wish to replace SSD. Would it be better? or any recommendation for this problem? **I faced this problem few days after buying this laptop.* Thank you!