Subpages are not found, although they should be indexed

Hi!

We have been working on a website for trekking tours for a little over a year. The goal is to collect the information about the tours - which are currently scattered all over the net - and make it available to the users. Thereby we enrich this information with many more data. Later a community is planned and much more. As I said, we are still at the beginning of the journey.

Now it is so that we already adhere very strongly to all the SEO recommendations. Of course, we are not perfect, but overall we do - I think - a pretty good job. Nevertheless, we have the problem that MyTrails does not rank as well as we would like. That's partly understandable, because there's a lot of competition for some keywords. But in part it is also not understandable.

Now I have noticed a few things:

• We have a spam score of 22%. We do not send out newsletters or similar! Is this value questionable or doesn't matter? How can we lower it?
• If you enter certain search terms, one of our pages should rank at the top: "Australian Alps Walking Track" and "MyTrails". By mentioning the name of our website, the corresponding page should be at the top. But this is not the case. Rather, it finds another page from MyTrails that mentions "Australian Alps Walking Track". However, when I search for the URL in Google Search Console, it states that the URL is indexed and everything should be ok.
• A similar behavior exists with many other combinations where Google actually doesn't give usable results, but we would have them on the website. E.G.: <> and <>. Here often completely useless SERP are preferred to our page, or our page is not found, although it should be indexed.

Does anyone here have a tip from you?

Many thanks in advance! Stefan