I have a Honda Acoord year 2002. The srs light is on, and, if you blow the horn it blows the fuse out, which also has something to do with sending the signal for the car to be put into gear, because once that fuse is blown the car will start but not go into gear. If I replace the horn will this fix the problem, or is there possible a short somewhere? Is the SRS light connected somehow to the horn? Thanks.

Yes, sort of. It's all wired via a spiral cable in your steeing column.
Most likely shorted there.

Thanks, so, should I just have the mechanic check that in the steering column without having them out it on the machine to check what's wrong, that's what they want to do which of course is more money!

With SRS you always have to see what the code is first, and of course you need the 'machine' to check that.
Most likely it will say short in drivers side squib circuit. In coincidence with the horn shorting a fuse, all the mechanic has to do is put 2 and 2 together.
Hopefully they will apply discount towards the repair. Some do.