Yes, the first step would be to apply the UV map or redo the UV map. The engine does not know which part of the texture goes where and at what scale, that is what UV maps have been invented for.
Of course it is complicated to recreate a UV map from a texture, you see normally it is the other way round: You paint the texture based on the UV map that you create first.
Where is the model from? Did you make it yourself or did you acquire it from somebody? If you got it from somebody, they must provide the UV map, it may be that it got lost on the way…
Solving the scaling issue is not a big deal. You just need to tell the material editor how to “tile” the texture.
Open up the material that the engine is created for you. Therein you will find the texture as an input to the base color, Pull from UVs and select TexCoord node. In the details tab tweak the U and V tiling values 
See the pic that i attached for you
But if the uv map is not proper you may be able to scale it down but will still not align!
And don’t lose patience It takes a while to learn how these things work. Watch a tutorial about UVs because it is very important!
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