Every plain vector space admits a norm - no matter of its dimension. If V is finite dimensional, it is normable, in the sense that you can use an isomorphism into Rn to pull back the Rn-norm .

Do all vector spaces have a basis?

Summary: Every vector space has a basis, that is, a maximal linearly inde- pendent subset. Every vector in a vector space can be written in a unique way as a finite linear combination of the elements in this basis.

Does every vector space have a proper subspace?

A subspace is called a proper subspace if it's not the entire space, so R2 is the only subspace of R2 which is not a proper subspace. The other obvious and uninteresting subspace is the smallest possible subspace of R2, namely the 0 vector by itself. Every vector space has to have 0, so at least that vector is needed.