How can i get an ignition interlock installed if i dont have a car?!

Think about it: you are implying that you don't need interlock because you won't be driving yet you are anxious to get your license back because... you will drive someone else's car and that's the one that will have the Interlock.

What car will you be driving once you get your license back? If it is someone else's vehicle and he/she does want the device installed on the vehicle , or if you have a vehicle that you plan to purchase, you need to request a hearing so that you can explain to the judge why you are unable to comply with the court order. Do not wait until the time to comply with the order has run!

You are required to have the interlock on a car that you operate when you blood alcohol content was .15 or higher. That requirement cannot be waived by a Judge. You will not be able to get a limited driving privilege, assuming you meet all the eligibility requirements, without that proof of installation and proof of insurance. If you are driving someone else's car then it will have to be installed on that vehicle, but that means anyone who drives the car, including your brother will have to deal with the device on the car for a year. You cannot drive until your license is reinstated or you qualify for a Limited Driving Privilege. I suggest you contact an experienced attorney in this area if you need further assistance.