.obj can be imported directly by default (assuming it's the standard Wavefront format you're referring to, which it most likely is). File > Import > Wavefront (.obj). Presuming importing isn't your main problem though.
Blender doesn't have a built-in way to simply export to web, though.
There are some (2 year old) plugins to convert models into web-ish formats such as .json, but then you need a web programmer to do anything useful with that.
Really, the web doesn't have a direct/easy way to 'just' show 3D models. There are a number of competing services/technologies trying to solve that, but none of them are totally simple/direct.
If it's just a wireframe, that's simpler. if there's textures involved, the problem becomes an open-ended one of how much data do you want on your web viewer. Fancy Shaders?
Things like 'three.js' and webpages using 'WebGL' are low-level systems for web programmers, not immediately useful to artists/end users.
The least technical way available currently is to use one of the services that allow web pages to show models in their own web viewer browser component, such as SketchFab or Verge3D. Verge3D is a successor of sorts to the discontinued 'blend4web'. Others may be available.
In either case, there are some hoops to jump through. Each has its own process to get data out of Blender. Checking those services' documentation would likely be your quickest way forward. I have not used either myself and can't make any specific recommendations.