I wanted to ask that I want to buy a condenser mic, I know it needs phantom power to work. So my question is will it work if i will connect it to a 3.5mm jack to my amp.
3.5mm mic jacks might (sometimes supported by a jumper or different sound card setting) provide "plugin power". It can power electret condenser capsules with the typical single-FET preamplifier and works, for example, for the surprisingly good stereo clip microphones that were available for Minidisc players.
Regular phantom power, however, is 40V to 48V and is never provided on 3.5mm jacks. You'll primarily find it on XLR sockets.
There may be electret condensers with 6.3mm jacks that can alternatively use plugin power or a single 1.5V battery inside. You'll probably fare better with clip-on mics for wireless setups (mini-XLR or similar) but you'll have to make sure the pinout is compatible.
Any mic advertised to be using "regular" phantom power will not work.
Not all condenser mics need phantom power. Not all amps/mixers provide it. If the mic in question needs it, and the amp doesn't provide it, then it won't work. Usually phantom power is provided through the XLR (Cannon) plug/socket. By using an XLR-jack adapter, the power may well be lost through the connection.
A microphone that requires phantom power will not work without it. Phantom power is a method to feed 48v to the microphone through the 3-connector XLR plug. You'll need to plug that mic into a preamp or mixer input that provides phantom, or alternatively various companies make a DI box that provides phantom power.