How has Prime Ministers acted like Presidents, but been severely Limited in doing so in British Politics?

-Personalising Election Campaigns can Damage Leaders if the Campaigning Skills are not on Point. May's Public Faith weakened after U-Turning on Party Policy on Dementia Tax -Spatial Leadership isn't Possible due to the Fusion of Powers. PM are eventually Reined in. May had lost all Control on the Payroll Vote. March 2019 saw Junior Ministers allowed to vote on the Indicative Vote Process over Brexit -Reliance on Advisors can damage PM's Credibility. After the Manifesto and Loss of Majority in 2017, May sacked Senior Advisor Nick Timothy and Fiona Hill -Ever since Iraq War, Parliament has become much more Assertive. Cameron failed to Persuade Parliament to vote for Military Action against the Assad Regime in Syria