l drove it yesterday and it worked fine. How do l fix?

jack it up and get under an inspect the linkage

A lot of cars have a mechanism (a brake sensor) that allows the car to shift out of park and into gear. It is possible that it has either been disconnected or has gone bad. On a lot of cars there is an override, but in a column shifter l could not tell you where it is. There might be a diagram online somewhere.
Look underneath your dash where your brake pedal is.if you see wires/connectors make sure they're connected all the way<---a start.

Make sure that you are depressing the brake when shifting. Since you drove yesterday Im sure thats not the case.
Try checking the shifter linkage next to the transmission, if ok then problem lies in the steering column. Next check the neutral safety switch and next the ignition lock cylinder. if it gets to this point you may want to get some pros help cause it can get tricky. Good Luck.
ASE Master Tech.
10 years

brake pedal sensor not working.

check your brake sensor it could be disconnected that is what hapen in those cars

also check your brake lights , are they working , it may just be a fuse , it happens on some cars

See if you have brake lights on when stepping on brake pedal,if not,check fuse of same.If fuse is OK,look at the brake light switch (at the end of the brake pedal),see if the 2 wires that plug in the switch still there,wiggle the wires to see if one is broken.Common problem since the travel of brake pedal flexing the wires and eventually broke them.