Whats the best inner page strategy?

I have about 80 pbn network that I have used for my home page, its sitting on page 2-3 for many kws. I have just completed more kw research and found some really low comp kws that may require a few links. So I have 2 questions:
1st: can I link from the same pbn site to both home and inner page? Is there a limit to how many links you can do for 1 site on different pages from a pbn site?
2nd: if I want to follow a cheaper alternative to rank lower kws, what links currently packs the most punch besides pbn, would it be manual web 2 with a 2nd tier? High profile links, manual 20-30 social bookmarks or what?

Some of my pages should rank page1 with just onpage seo as my site has good DA.

Thanks in advance, sorry for any errors as I am sending this from my phone.