Can I get a tooth replacement for my right upper 2nd molar?

If you want to get an implant in the second molar site, you have to make sure you have enough bone in that area below the sinus.  I would suggest getting a full set of photos, models of your teeth, and 3D CBCT scan. First see if it makes sense to get an implant back there.  If it makes sense for you and your bite, esthetics, see how the bone looks.  You can always get a sinus lift, etc.  But I would suggest really deciding if you need / want a second molar replacement.

You cannot have a bridge attached to that implant nor have 2 teeth done on it. If you have no tooth below then there would be no reason to do an implant. Because the tooth has been missing for a while , the sinus has probably expanded into that area, making it impossible to do an implant without a sinus lift and bone graft in that area. Why would you want to go thru that and the expense for little to no gain? Just food for thought