Solvent is, in simplest terms, something in which you dissolve another substance (also called as solute) and this mixture will yield what we know as a 'solution'.
Solvents are generally liquid (water is the most common example), but can also be gas or solid. Solutes are the materials that are dissolved into solvents and we end up with solution.
Some examples of solvents are water, ethanol, toluene, chloroform, acetone, milk, etc.
Examples of solutes include, sugar, salt, oxygen, etc.
There are numerous examples of solutions. For example milk (solvent) and sugar (solute) makes sweet milk. Air is made up of gases (oxygen, nitrogen, carbon dioxide, etc.). Alloys are made up of metals, for example, bronze is made up of copper and tin. River water contains water (solvent) and dissolved oxygen (solute).
You can find many other examples of solvent, solute and solution in all aspects of our lives.