Whats the weekly allowance a person is allowed to spend on their account or canteen???

It depends on the facility. In federal, the amount is $320 per month ($370 in November and December) on commissary items.  This does not include over-the-counter medications, copy cards, or postage stamps. In state prison, the weekly amounts range from $40-60. In the county jails it is about $75 per week. The private prisons like CoreCivic or GEO also allow $75 per week.