First off, your English isn't terrible, especially considering that people are cocntributing from every corner of the earth.
Second, I believe a lot of MIXXX users are not DJ's either -- as for me, I've never done this professionally, at least as a livelihood, but I've played music at shows and people love it and demand more, so I must be doing something right So you can call me one I suppose. Someone in Clearwater, Florida, began calling me the "Spin Doctor" and the name stuck.
Two microphones? Your best bet is going to be a mixer. Not the DJ mixer that provides for two turntables with a crossfader, but a 6-channel, 8-channel, or whatever, mixing board; enough channels to fill your needs.
I don't know your budget or your total needs, but I've got a handy little board that's a Yamaha MG102C. It's a small portable board that performs really well and lets me do all sorts of work, both production and for gigs. Don't remember the price, couple hundred I guess. For hobby use you might make a visit to your local music store and see what they have in the used, trade-in department. Best bet for headphones is to use two jacks from two hardware sources, or get some kind of splitter -- seems these are around for very little money. Generally they have volume controls that allow each user to adjust.
Is your hobby radio a Part 15 transmitter, or some sort of computer streaming audio? The output of your mixer can go directly into a part 15, or to another computer. Two computers seem like a lot of hardware, but they can be had for cheap or free -- people trade them in every year or two, and the old ones often get tossed. One of my workhorses is an old 32-bit XP that simply didn't get traded in.
In a way, all this seems a bit scary. Not that long ago a radio console meant spending tons of money, and home equipment didn't even come close in performance. Nowadays with a computer and some spare junk, one can assemble a rig that blows the pants off hardware that was studio standard just a few short years ago.