Fan is running compressor is not starting . How can I fix it at home right now

Could be a lot of things. Low Freon, bad contactor, loose wire. You will need to have someone check it out.

I would start by checking the compressor capacitor. Does it look 'bulged' or leaking? Very common for caps to go bad, and they are cheap and easy to replace.

Outside fan and compressor are not, put a new capacitor in last week lasted stopped working