2D Pixelated game multiple questions!

Hello everyone,

I have some questions related to making a pixelated 2d game. I know it is possible, but I got no clue at all about how to make it.

So a little about what kind of game I was hoping to make. The player is one of the people that survived the zombie apocalypse, and the player will need to survive by making decisions. He start all by himself and has to give his character a task and then once he gave himself a task and later all of his fellow survivors click next day. It will give a log for each character. Like if he found supplies or got attack by zombies. Which will be randomly by the game. If the player is giving tasks it will open a world map which is randomly generated with your settlement (which may be upgrade-able to have more survivors etc.) in the middle and cities and other things also on the map randomly. You click on the place you want to go and say what the person should do there. Depending on how many chunks away the task is, the more fuel it costs which also be randomly found. The goal is also randomly, like get X amount of survivors or search X amount of cities. I got some basic texturing done for the map part and that is all I got, now I got the following questions:

1. Even though it is possible to make the game in Unity, wouldn't it be easier to use another program?

2. How to make a randomly generated map seamlessly sticking together?

3. How to make the textures be on the right spot they should go without having trouble about different monitor sizes.

4. Layer the textures right.

5. make the textures not look blurred.

I have this texture (see below) on a quad and want to make them placed next to each other (with the dirt side only on the bottom ones being shown). Of course I have some different looking ones. But I think once I can generate those next to each other I can let them be randomized by myself on textures.

How can I make those fit perfectly next to each other with a code to make them be in a X by X shape where I can set X myself. I also had the problem with placing them by myself because some of those will be on top of others. I might can fix this by putting some a little more towards the camera. Anyway I could make a map with those textures, but I can't figure out how to let them be made with a script. I was thinking of starting at the top one and make the second one be placed X towards the left and X down, third X to the right, fourth X towards the left and X down. and by each time down also X forward so the layering is right. It sounds easy but I got no clue how to do this. The quads are 163x88 just like the texture. The texture:

I will provide more information if needed and I will be very thankful if anyone can learn me some more about how to make this. Thanks for reading and hopefully someone can help me.