When setting up a new computer, you firstly need to establish all the necessary connections. Then install an OS if it does not already have one or you aren’t comfortable with the default one.
After this, make sure that the bloatware (if any) is removed since those would slow down your system in the future. The next thing to do is to set up passwords and the antivirus on your PC.
You also have to configure the desktop as per your needs, like setting up wallpaper, creating folders, etc. Next, you should install the required software and applications. When all this has been done, connect your email and other accounts to it.