'Would' has two core meanings. First, it is the past form of 'will' mainly when you report what someone said or thought: She said she would call later carries I will call later into the past. The same past sense can also describe a real failure: The car wouldn't start this morning, where wouldn't is simply will pushed into the past. Second, 'would' points to the result of an event you are imagining, as the example below shows.
If you went to see him, he would be delighted shows the imagined use. The visit never happened; would points to its imagined result.
Your friend asks what you'd change about her haircut. You say, She'd look better with shorter hair. You are picturing the result, not describing something that happened.
The same imagined job appears in everyday talk. A friend hesitates before asking for a raise, and you say, The boss would say yes. The raise is only a picture in your head, and would points to the result in that picture.
One nearby use to keep apart: in reported speech, would is simply the past form of will. She said she would call later. Nobody is imagining an outcome; she said I will call later yesterday.
Compare that with the imagined-result picture: She would call later if she had time. Here the call never happened; would points to the result in an imagined situation.
A quick check helps: if the sentence reports what someone said or thought, it is the past of will; if it paints an unreal picture and its result, it is the imagined use. Same word, different job.