Install AnyMerge Docs add-on from marketplace.
Create a sheet, put there header columns and data rows. Make sure you have switched to the sheet in order to be able to configure it.
Choose an output folder where documents will be saved.
Create a template and put there merge fields. If you want to merge text values only you can apply various styles to the merge fields and add-on will replicate those styles.
Next step is to configure mapping between all merge fields in the template and columns.
Final step is to adjust output configuration. You need to set at least document name and choose a column. Values from the selected column will be used as filenames.
Hit the GENERATE button.
Happy merging :)