I noticed wanikani used in one example 見上げる and translated into “To look”. Why don’t we have this vocab in wanikani and what does あげる mean when it comes after a verb, does it mean upward?
What example was it? 見上げる specifically means to look up to/at something, both in the literal sense and the figurative sense (as in, to admire or praise someone/something). The “up” part of it is what’s conveyed by あげる in this example, and as you may expect there’s also a counterpart, 見下げる (though it seems that only works in the literal definition of looking downward at something).
You will often see verbs connected together by their stem form in Japanese. This will often combine the meanings (but some don’t make a whole lot of sense), and this is one example of it.
For instance, 見上げる means more “To look up” than “To look”. A lot of other verbs attach to 上げる (search *上げる on jisho.org for full list), such as 読み上げる, 差し上げる & 申し上げる.
As for the WaniKani side of it; they can’t go around teaching every piece of vocab around (that would bloat the website SRS, and kanji is their main purpose either way). They have to pick and choose vocab in a way which balances usefulness and kanji utilization. In this case 見上げる didn’t make the cut.