You won't be able to put a proper fixed cog / lockring setup on that hub. The best you can hope for is a "suicide hub". Fixed / track hubs have a step in the threads to allow the lockring to be fitted. You can see what I mean here: fitting a fixed gear cog and lockring
It looks like you have the right(ish) tool for removing that freewheel, but you'll have to remove the hub axle first because yours is solid not quick release. This might not be a good idea if you aren't sure what's inside a cup and cone hub.
You won't be able to put a proper fixed cog / lockring setup on that hub. The best you can hope for is a "suicide hub". Fixed / track hubs have a step in the threads to allow the lockring to be fitted. You can see what I mean here: fitting a fixed gear cog and lockring
It looks like you have the right(ish) tool for removing that freewheel, but you'll have to remove the hub axle first because yours is solid not quick release. This might not be a good idea if you aren't sure what's inside a cup and cone hub.