You need to start slow thats my first advice.
I lifted competively for years in weightlifting, i just went back to the gym and i still have my strength but my cardio is no good , i lifted for strength though and eventually had to get 2 knees anthroscopys because i done too heavy squats over the years,i dont do them at all now
I dont know your weight or height though
To achieve bulk you are going to have to lift heavy and eat more protein foods and even eat more
At 55yo my advice is not to train everyday in weights as you will tire out easy,same results can be done 3 to 4 times a week
If your lower weight and fast metabolism then u dont need to do much cardio if at all
Concentrate on 3 to 4 times a week , do body parts separately, eg arms and shoulders Saturday,legs sunday , chest Wednesday etc , it should take you no more than a hour if that
You want bulk instead of strength then do more reps at a lighter weight after the first set, go heavy first set,then lighter ,try to feel a pump in your arms and work the muscle,if you cant feel a pump the weights too heavy.
Sometimes doing lighter weights say for arm curls works the muscle better than the heavy weight where i see sime guys jerking the weight upwards instead of concentrating for muscle .
Do 4 sets x 8 , last set go over 8 reps
If i was you and im not you at 55yo i would go for fitness and strength training rather than trying to bulk up or look muscular big
You need to perservere ,sweat and train hard , 3 to 4 times a week is enough at your age
And yes you can find personal trainers who train diabetics, eg Fitness First have them
There are bodybuilding forums too on the internet you can ask