First... why you installing ESXi 6.0.0 which is stone aged and years behind? There is 6.0latest, 6.5 and for 1.5 years now we have 6.7 where the 6.7u2 comes out a couple of weeks ago.
For managing a single Host with a browser there is the "Host Client" which runs behind https://ip-esxi/ui but i cant remember when VMware starting shipping the Host Client together with ESXi because the "Host Client" was born in the ESXi 5.5 erea as a fling (ESXi Embedded Host Client ) and was seperate for some time. In that period of time a lot of people use the Windows C# vSphere Client to manage a single Host. This vSphere Client was depricated since 5.5 but was usable up to ESX 6.0latest.
The "Web Client" was that browser GUI which comes with the vSphere vCenter (Windows (is dead now) or Appliance(VCSA)) which can be reached under https://ip-vcsa/ and than click Web Client(Flex). With VCSA 6.5 they introduced a HTML5 Version too to get rid of the WebClient which is a Flash Version and not supportet well from modern browsers.
With 6.7 they start renaming all the GUI to confuse beginners like you :smileyhappy:
If you would like to stay with 6.0.0 i suggest to download the old windows vSphere Client to get access to the ESXi and than check out if the Host Client is already installed ot not.
Regards
Joerg