Re: To be honest ...
If there is any evidence that Biden did the things you attribute to him, then Trump could have directed the Department of Justice to investigate him. He could have appointed anyone he liked to head that investigation. (I keep hearing that Rudy Giuliani is a great corruption prosecutor.) That's what he would do, if he were serious about investigating corruption.
But Trump didn't do that. Instead, he called the president of a foreign country -, a country that was at that moment particularly vulnerable and dependent on US aid that had already been duly voted through by a bipartisan consensus in Congress - and made it clear that they wouldn't be getting this aid unless they made a public statement that appeared to incriminate the Bidens.
(Whether or not there was any actual investigation, or whatever the outcome of that investigation may be, was completely immaterial to him. All he wanted was the announcement.)