Because the hiragana ends with an う sound, you know this word is a verb. The kanji itself means bind or tie, so the verb vocab version is to tie. Tying is also a great way to connect things, so this verb sometimes means that too.

At its core, 結ぶ is about bringing things together and creating a connection. It can be physical, like tying a string, but it's also commonly used in abstract ways, like forming relationships or establishing contracts.

Since this word consists of a kanji with hiragana attached, you can bet that it will use the kun'yomi reading. You didn't learn that reading with this kanji, so here's a mnemonic to help you:

You decide to tie a ribbon on a moose (むす). Why? You're going to give it as a present to someone you want to connect with. Nothing says "let's be friends" like a moose with a big, fancy ribbon tied to it. Now if only this moose would stand still so you could tie a proper knot…