Infrastructure Upgrade from 4.1U3 to 5.5

Hi,

I plan to upgrade my system architecture :

2 HP DL380G7 with ESXi

1 HP P2000 with 3 datastore

1 vSphere Essentials plus 4.1U3

I want to upgrade to vSphere Essentials plus 5.5 but I don't know how to proceed.

Should I migrate all my VM on a different server to upgrade the DL380 servers ?

Should I create temporary datastore on my P2000 for the upgrade ?

Thank you for your answers