Steps:

1. open startup folder
2. place shortcut inside

1. Easy way:

Press Windows+R on keyboard, in opened window type shell:startup and hit enter

1. Other option if solution above doesn't work

Open file explorer hit this pc, open Users folder, then open user (or your username) folder.

Now click at bar above folders which should look like "local disk (C:) > Users > user>"

After you clicked bar it should look like "C:\Users\user". You need add "\appdata" so it would look like "C:\Users\user\appdata" and hit enter button.

Open Roaming folder, then open Microsoft folder, then Windows folder.

Now you need to click again at bar above folder it should look like "C:\Users\user\AppData\Roaming\Microsoft\Windows".

This time add "\Start Menu" so it would look like "C:\Users\user\AppData\Roaming\Microsoft\Windows\Start Menu" and hit enter.

Open programs folder, then open startup folder.

2. Move shortcut of program that you need from desktop to startup folder then click on it and make another desktop shortcut if you need it on desktop.