Question Setting up Thunderbird in Win 11

I was all set to add my Full name, email address, and everything appeared as it should with account server and its numbers. When i get to the bottom of the 'page', there is no button to clinch the entry. Previous window systems always follow up with ..."do u want to add anothe account", but i never got that, nor the one i just completed. ..I have the OCtober updated.
 
I HAVE THE WIN 11 23h2 VERSUIN, ABD u WEBT TI tASK mANAGER AS INSSRTUCTED, END TASK ON fIREFOX, McAfee and Firefox still appeared upon boot up. As for Microsoft, there were numerous links to them and i did not know which one to choose, or am i suppose to choose all of them? What is this about Dell and FF not being compatible as someone here said? I believe i did make Ff my default way back when i firs got this refurbished laptop. a year ago.
 
Yes, about FF and Thunderbird, but the gist of this thread was about being confronted with all that i had mentioned above when I boot up. I mangaed, so far with task Manager disabled McAfee. which I never used....but like I said I see numerous Microsoft process's and can't seem to stop it pestering me everytime i make a movement., and FF still appears at bootup even after ending task.