Hello,
Of course, the recommendations are different for each person according to age, gender, training conditions and some other variables.
The best supplements for weight gain in general:
Creatine Monohydrate
Whey protein
Carboproteins
Supplements contain EAA or essential amino acids
Besides, the beta-alanine supplement helps your exercise ability due to the reduction in fatigue.
Also, because of the high carbohydrates, gainer supplements provide energy for training and thus help you gain weight.
Thank You