You can't just delete the forms using tax tools because the underlying data will still be there and it will just re-create the forms immediately.
First, you have to go to where each category of income was entered last year (rental income for the rent house and I guess business expenses for the van?)
Then you go to each of those items and click the little trash can to the right to remove them.
I should caution you, however, that both of these items should not be removed that way. You should tell the system what you did with that rental house, whether you sold it or converted it to personal use, and the same with the van. If you sold these things you may owe taxes on them and filing a tax return where they just disappear after they were on there last year can be a bad idea and really delay processing of your tax return.
@sfd2