Could he EO out all the parts he does not like. I would imagine that he might actually read this piece of crap bill!
"Signing statements" are used to declare interpretation of statutes. I doubt he reads it himself - budget bills are dense legalese. Staffers read it and provide summary for the president. Going by how the politicians describe the laws, I am certain that it is not uncommon for a staffer to compose a misleading summary. I expect Trump does a bit of "spot checking" and demanding explanation.
The sheer volume of legislation and regulation is such that it is literally impossible to read all of it - probably literally impossible to read 5% of it, if all you did was read full time.
Interesting question. We have no idea. We sure need the line item veto at his level.