You can use the old Bollywood songs which are available on Youtube for personal use. But if you use the songs not for own use but for playing it somewhere else.not sharing it online anywhere) you must get permission from the copyright holder to use any music on YouTube. you need a mechanical license.
The using of the any recording of a previously released song by someone who was the original artist or composer. A license is the agreement between you (the artist) and the publishers (owners of the composition) that allows you to play the songs recording in exchange for royalties.
You can get the license from the IPRS ( Indian Performing rights society) where according to section 38 of the copyright act, Any person who uses the songs of the owner for personal use or for commercial or non commercial use, will have to take license from IPRS which grants license to the users in exchange of royalties which has to be paid according to the length of the song which you are paying.
It is paid for the performences which are live stream or are paid through electronic records.You need to get it registered under section 38 of the Copyright act.
Reference: section 38 of the copyright act