Will a lot of chewing of foods or hard gum cause a reduction in bone in the jaw and ramus? and if so why? if this does occur will the bone ever come back or is it permanently lost and will the person have to get an implant later on to rectify issue?

Multiple questions: Bone exists to buttress stress. If a tooth has been removed the associated bone will resorb. Surgical procedures are available to replace missing bone to be able to support an implant, but if adjacent/opposite teeth collapse into the extraction space replacement may be complicated. Chewing strengthens bone, gum disease weakens it. See Dentist now for long-term treatment plan.