Awesome Fonts slowing down site pagespeed significantly

v1.5.5f template Westminster New
and
v1.57b template Westminster New

css/font-awesome.css is aparently slowing down FCP and LCP significantly (by almost a full second which is relatively huge) which is adversely affecting status of mobile pages in core web vitals, i.e. resulting in zero good mobile url's which in turn is seemingly affecting overall Google rankings.

Google suggests the following as a fix;

Resources are blocking the first paint of your page. Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles

Is there a specific Zen Cart fix for this, i.e. is there a plugin that can apply deffering of non-critical JS/styles? or can something be tweaked to offset this that someone like me with limited (close to zero) coding skills can attempt?

I couldn't even find the file css/font-awesome.css via site developer or just searching via ftp client so I couldn't figure out how it works and no idea if it is template specific etc.

I would very much appreciate some assistance with this.
cheers, Mike

this from the v1.5.7b version site

URL Transfer Size Potential Savings
…css/font-awesome.min.css(maxcdn.bootstrapcdn.com) 7.8 KiB 930 ms

this also is a major time consumer !!! ...

/jquery-3.5.1.min.js(code.jquery.com) 30.6 KiB 1,080 ms

Font-awesome is loaded off site.

https://netdna.bootstrapcdn.com/font-awesome/4.0.3/css/font-awesome.css is yours.

obviously an older version

Why that template (and others) insists on loading a local copy of a (what could be cached) CDN version is beyond my ken.

many thanks dbltoe for responding.

To put things in perspective - I am trying, within the limits of my abilities, to optimize the performance (and hence rankings) of my sites. I realize page speed is not everything but it is a component of SEO that can have an effect on performance - if all other aspects are up to scratch then why suffer unnecessarily from slow page speed?

In using admin/tools/developers tool I did establish that css/font-awesome.min.css is loaded off site however I have no idea how critical it is to the site in general and if not critical then how to isolate/disable it - or as lat9 has suggested, have it loaded into cache maybe? It is impeding page speed and I'd like to correct that impedement if possible.

So on dazzlerscliponearrings.com.au - v1.5.7b using the built-in responsive-classic template - I do believe I have most other technical aspects at a reasonable level. I have tidied up html and reduced image sizes and yes there is more that can be done - i'm not looking for perfection though, just a good performing site. As it so happens I have managed to get a 97% page speed rating for some of my still v155f sites, but struggling with this v1.5.7b site

There are other jscripts that are also affecting page speed;
/jquery-3.5.1.min.js(code.jquery.com) 30.6 KiB 1,080 ms .... this is the worst of the bunch at over a full second - cannot find this in the list of jscrits in templates to attempt to delete it and see the resultant effect so I assume it is like awesome-fonts, loaded off site.

I can only assume that both css/font-awesome.min.css and /jquery-3.5.1.min.js are critical to the function of the platform and if that is the case is there indeed a solution to their effect on slowing down the site?

Google are suggesting 'Consider delivering critical JS/CSS inline and deferring all non-critical JS/styles' however (aside from not being sure how to do this) from comments in the forums I believe that doing this will affect some critical aspects of those jscripts .... so not sure.

The other major culprit affecting pagespeed is Initial Server Response Time - I am hoping if the above jscripts are managed more efficiently then server response time will reduce proportionally.

So any guidance on solutions will be much appreciated.

cheers, Mike