You can use different web pages to merge files if you want to merge a different kind of files into a pdf file, I recommend this web page https://www.filesmerge.com
In this web, you can combine, a different kind of files, like “Pdf”, “Word”, “Excel”.
1- Choose your destination file, here we chose pdf file as our destination file.
2- Here you can choose your file from your computer or you can type the address of your file. I am going to add 3 different files, with a different type. excel, word and pdf.
3- When you upload all of your files, click on “merge” key.
4- After the process of merging was finished, click on “download”.
5- Open your file and click on print.
6- Save your file as pdf.
7- Here you can specify the location of your file in your computer.
How to Merge Pdf Files Online.
If you want to merge only pdf files, you can use https://www.pdfmerge.com.
NOTE: you can use this site only for merging PDF files.
1- Upload your pdf files and click on “Merge Files” key.
2- Download your file.
3- Print your file and save it as pdf.
4- Save your file on your computer.
In the how to merge pdf files with google drive page, you can see, how to merge pdf file with google drive.