How would I make meshes such as a bush or something for Unreal Enjine 4. Would I have to use an external program to make meshes? If so, what program. Thank you in advance! 
to make a mesh yes in most cases that requires a 3d modeling software such as blender, maya, or max. there are ways to convert bsp to mesh and procedural generation but most meshes are made in modeling software. there are also many other programs out there for creating assets but the 3 i mentioned are common and versatile.
Ok. Thank you and I was also wondering how would I import the meshes into UE4? Also which program do you think is good for a beginner like me?
Blender is not technically for beginners but it gives you so much room to grow. You can skip Max/Maya.
how would I import the meshes
Export them as *.fbx and:
- import them via the content browser - there’s a button for that
- or drag drop the files into the content browser - you’ll get the import prompt
- or drag drop into any of the project folders - you’ll get the prompt, too but keeping the original files in the project folder may not be desired, depends on your workflow
More info:
Ok thanks!
yea blender as with any modeling software has a learning curve and its not exactly beginner friendly. it can be done however, its where i started out with modeling and theres a ton of tutorials out there for beginners. i cant recommend enough channels like blender guru, Grant Abbitt, and Sebastian Lague. those three have beginner tutorials on using blender in general, character modeling, making basic props, and sculpting. theres many more that id like to mention as well but it would take awhile.