Website optimization and acceleration or CDN?

Question

CDN

Hello, there was such a question, optimization and acceleration of the site, or all the same CDN.
The site is on American hosting, so let's say the site itself does not weigh much, but the download is very long, the content of the site is delivered for a long time up to 7 seconds, for our time it is a very slow site. Although, as I write, the site does not weigh much, does the site need optimization and acceleration? Do I need to write to specialists in this field in order to speed it up or, after all, give up on CDN?

I wanted to ask your advice, what is the point of speeding up and optimizing whether the site will load faster or not? All the same, American hosting, I'm still inclined towards CDN, I would like to hear your point of view or 2 ways to do it at once? But I wouldn’t want to spend a lot either, is there any sense for a specialist to write or immediately connect a CDN?