It depends what OS has previously been installed on the laptop. You should be able to boot into Internet Recovery Mode using Command + Option + R to access the online macOS installer. In theory it should launch the macOS 10.13 High Sierra installer, but sometimes it will only launch the installer for the OS which originally shipped with the laptop from the factory. If macOS 10.12.6+ has never been installed on this laptop, then I'm not sure what macOS will be accessed (if any).
You can also create a bootable macOS 10.13 High Sierra USB installer using the instructions in this Apple article:
https://support.apple.com/en-us/HT201372
You will need to first use Disk Utility from within the macOS installer to erase the new SSD as GUID partition and MacOS Extended (Journaled). After erasing the whole physical SSD, quit Disk Utility and select the "Reinstall macOS" option.
Here is an Apple article with some useful special startup key combinations:
https://support.apple.com/en-us/HT201255
Make sure to always have frequent and regular backups.
Edit: The instructions to "erase" the whole physical SSD is for macOS 10.11 to 10.13. "Erasing" the drive is equivalent to partitioning & formatting a drive in Windows or Linux. If you are installing macOS 10.6 to 10.10, then you will need to partition & format the whole physical drive using the instructions in this article:
https://www.owcdigital.com/assets/support/support-formatting-and-migration/Mac_Formatting_6-10.pdf