How to calculate Taxes into future valuation models of businesses?

Hi guys,

I'm trying to make a 5-year valuation model of Tesla's business, but I'm not sure how much taxes they will have to pay. I see that Trump lowered the corporate Tax rate from 39 to 21%, but when i research apple and amazon taxes it seems they are not paying anything. Also biden wants to increase this percentage, but does this percentage even matter if big businesses just avoid them entirely anyways?