My past employer is not giving my salary, gratuity...

If the employer refuses to pay the salary, the leave salary, and the end-of-service gratuity, the worker can file a complaint with the Ministry of Human Incoming and resettlement against the employer in order to obtain his rights, and that the leave salary is calculated according to the basic salary plus the housing allowance also, the end-of-service reward is calculated at the rate of twenty one days for each year of service from the first five years and thirty days salary for each year exceeding that.
If the employer refuses to pay the salary, the leave salary, and the end-of-service gratuity, the worker can file a complaint with the Ministry of Human Incoming and resettlement against the employer in order to obtain his rights
Here is the text of the UAE Labor Law, related to your inquiry:
Article (75):
A worker shall, for each year of service, be entitled to an annual leave of not less than:
1.      Two days a month, where the worker’s period of service is more than six months but less than one year.
2.      30 days a year, where the worker’s period of service is more than one year.
Where a worker's service is terminated, he shall be entitled to annual leave in respect of fractions of the last year.
Article 78
Each worker shall be entitled to his basic wage and the housing allowance, if applicable, in respect of his days of annual leave. Where it was imperative for the work interest to put a worker on duty during all or part of his annual leave, and if the leave days on which he worked were not carried forward to the following year, the employer shall pay him his normal wage plus an allowance in lieu of leave, for the actually worked days, calculated on the basis of his basic wage. In no case shall a worker be made to work during his annual leave more than once in two successive years.
Article (132):
A worker who has completed one or more years of continuous service shall be entitled to severance pay at the end of his employment. The days of absence from work without pay shall not be included in calculating the period of service. The severance pay shall be calculated as follows: 1. 21 days' wage for each of the first five years of service. 2. 30 days’ wage for each additional year of service provided always that the aggregate amount of severance pay should not exceed two year's wage.
Article (133):
A worker shall be entitled to severance pay for any fraction of a year he actually served, provided that he has completed one year of continuous service.
 
Article (134):
Without prejudice to the provisions of laws that grant pensions or retirement benefits to employees in certain firms, severance pay shall be calculated on the basis of the wage last due for monthly, weekly and daily paid workers, and on the basis of the average daily wage referred to in Article 57 hereof for those paid on piecemeal. The wage used as a basis for calculating severance pay shall not include whatever is given to the worker in kind, housing allowance, transport allowance, travel allowance, overtime pay, representation allowance, cashier’s allowances, children education allowance, allowances for recreational and social facilities, and any other bonuses or allowances.