header HEADER.TPL missing from Themes Folder

[New Pop]

Hello guys,

I'm new biz without experience of creating web stores or smth like that. I installed Prestashop wih 1&1ionos ,one click app install and that was pretty easy and smooth and I was making some changes, installing modules. Basicly I was going into Prestashop to get familiar. More less everything was fine. Even web site checkers showing good scores on performance. 
But today when I wanted to add code snippet (add this app) "social media buttons" into head of header file I coudnt find that file. I read couple of solved issues related to this one but it didnt work. I will attach screenshots of file that I found called header.tpl but it was in folder /Themes/classic/templates/_partials and as per my basic knowledge header.tpl file looks different.
P.S. Before Prestashop I had store for abouth month with Bigcommerce but I found Prestashop for me much better than Bigcommerce and its free. I'm telling you that because it is same domain so because of possible mixed up files I dont know. 
Screenshots how it looks like header.tpl that I found. I dont see any head or body line where I could paste code. 
Please if you can help me I would highly appreciate any assistance.
 

[JBW]

You are most probaly looking for head.tpl, not header.tpl. Anyway for social media links there is a module which can you assign to correponding hooks, no need to edit any files.

[New Pop]

Both head.tpl or header.tpl looks almost the same without head line where I could paste or edit. I know for some modules that could be used instead of editing but somethings not right in mentioned files and thats the reason why I asked for a help or advise. 
Thank you for your advise and I will try with modules to see how it works. Thank you JBW one more time.
Cheers