Yes you can. The treatment is intavaginal using RF energy to stimulate better blood flow, nerve endings and above all stimulate new collagen synthesis and align the old.
Its been 2 months since your surgery. wait a little longer and you might see an even better outcome. The reason, we wait before we decide any procedure may benefit form a revision is because tissues take awhile before you see the final outcome. This is why your doctor has advised considering one a year later - you may actually decide you don't need one by then.
Prior to any laser treatment for skin lightening, the skin needs prep yes, but other factors matter such as area being treated. The prep creams/ lotions required are not sunblock creams and will be advised to you by your doctor. The treatment is a process that can take months and compliance here is key. Please discuss the whole time frame involved and the do's and don'ts (including what creams/ solutions need to be applied) with your treating doctor
Thermiva/ RF can give you some effect but without a Fat grafting or filler+PRP, the effect maybe sub-optimal. You need to consider the cost involved with multiple sessions that would be required. Toning up thighs and buttocks will be helpful too.