Phrasal verbs are multi-word verbs—action phrases—that take on different meanings from the individual words that make them up. These word groupings have an idiomatic meaning: the phrase's meaning is not always obvious. For example, someone might work for a long time on a project but they will eventually "give up," meaning they "abandon" the task. Structurally, they are formed as "Verb + Particle." Phrasal verbs are often associated with the casual spoken word versus formal writing. Moreover, phrasal verbs often have literal versus figurative meanings.
Collocations (also known as co-occurrence) can be thought of as "word partnerships" or "word chunks." To native speakers, these are just natural, predictable pairs of words that express meaning. For example, people might discuss the weather and talk about "heavy rain," not "strong rain." Learning collocations is a good goal to set for yourself because it will give you native-like fluency in English over time.
"As someone that must grade a lot of English papers written by Francophones, I see a lot of phrasal verb errors. As the English Club website rightly points out, phrasal verbs are "Phrasal verbs are usually two-word phrases consisting of verb + adverb or verb + preposition." I am compiling a list, here, of phrasal verb errors often used by Francophone ESL students.