Here's the details from a popular online encyclopaedia website which I would expect to be factual and relatively neutral on important public subjects like this :

https://en.wikipedia.org/wiki/Mueller_report

Note the second paragraph:

"... the report states that Russian interference in the 2016 presidential election was illegal and occurred "in sweeping and systematic fashion" but was welcomed by the Trump campaign as it expected to benefit from such efforts. It also identifies links between Trump campaign officials and individuals with ties to the Russian government, about which several persons connected to the campaign made false statements and obstructed investigations."