Houseplant Figs (Fiddle-leaf as well as Weeping Fig and others) grow best when allowed to get fairly dry between soakings. They do not thrive if kept too wet. Overwatering is a common problem. Make sure your container has drainage holes and is not sitting on a saucer that holds water (empty the saucer so it doesn't keep water in it). Feel the soil moisture about 2" down beneath the surface to make sure it's dry before you water again, then water well.

Plant edema is caused by an imbalance of water in the soil and water moving out of the leaf - usually this occurs when the plants are being over-watered and evaporation and transpiration aren't keeping up with dispersing the excess moisture.

Since leaves do not heal, any afflicted with edema scarring will not repair themselves following a new care routine and may shed early. 

Gradual yellowing and shedding of older lower leaves is normal as plants mature - they do this mainly as new leaves are being grown. Plants that are under-fertilized may do this more drastically, but this is challenging to ascertain as the sole cause since other stresses can manifest in the same way. (Such as over-watering, even when it doesn't cause edema.) 

Dying leaves can be clipped off, but if possible, it's best to wait until they fall naturally so the plant can resorb what resources it can from the leaf. If the fig hasn't been fertilized in months, it could probably use a dose of general-purpose houseplant fertilizer (for leafy houseplants, or otherwise not a "bloom-booster" formula).

A new houseplant may lose some leaves as it adjusts to a new environment. Bringing it home also often results in some bruising, with the result being brown areas on leaves. This should be minimal.

Ellen