instead of setting a weight objective, if you plan to exercise, its a good idea to set a bodyfat % goal, since gaining muscle and losing fat both work towards that goal and its more representative of your general health state
as for an exercise routine, you could do something more hypertrophy oriented since it burns more calories and is generally easier for starters because you have a smaller chance to injure yourself and complement that with some cardio or HIIT if you want to lose fat more effectively
depending on how much time you have, you could do a 2 day body split such as upper/lower body
For upper body, would recommend incorporating something like
Bench press (for pecs+triceps)
Overhead press (deltoids+triceps)
Lat pull down (lats+biceps)
Cable Rows (Lats+biceps, different angle)
Lower could try doing
Squats (if capable, great core work aswell as quads, hams, glutes, back extensors)
A deadlift variation (especially if you cant do squats)
Leg press if all else fails, its not very functional but will help develop muscle and burn calories for sure
Could do 3 sets of 10 for every exercise, if you have more time can add some exercises for those muscle groups or increase the number of sets
The key to body recomposition is a combination of exercise and diet, diet only will get you skinny fat at best and you'll lose weight much slower aswell as lose some muscle mass
To do that routine you'd best subscribe to a gym, generally any gym will do, and if your fiancee is interested in getting in better shape, bring her with you
