A lot of people meditate these days, but many complain that they are unable to focus well. Many people ask how to focus while meditating and what to focus on. There are several options.
If one has an imaginative mind that can visualize God in a specific male/female form, one can visualize and focus on that form. One can imagine God as a specific kind of light and focus on that. One can focus mind on a particular point in the body (e.g. a point in the middle of forehead or in the heart, or at the top of head). One can focus on the sound pattern of a mantra. One can focus on the breath (in and out).
There are several options and one can use whatever works the best for one. Rishis of Sanatana Dharma never said "only this" or "only that". Saying "only that" or "only this" is the modus operandi of modern religions that came during the dark age of Kali yuga. As people have different tastes and aptitudes, rishis gave umpteeen options!
The key is to not get frustrated if mind loses its focus. It is after all the nature of mind to wander!
If one gets agitated on realizing that mind has wandered from the focus point, it does not help and that agitation can instead compund the problem.
Getting agitated and worrying too much about the loss of focus in meditation is like a speaker engaging in a fruitless debate with a heckler!! That just destroys the speech. Instead, let the heckler do his yelling, ignore his provocation and continue with your speech once he is done!!
Similarly, it is better to simply take cognizance of the fact that one lost focus and calmly resume the effort. Even if distraction happens again and again, resume the effort each time. Eventually, after thousands or millions of such instances, it will click.
Just as a child may fall hundred times trying to walk on one's own, a mind may wander thousands of times before it can focus perfectly on a mantra. But one has to keep trying.
Iinstead of trying too hard and with too much force/effort, try to relax and keep trying calmly. Calmness and persistence are better allies when it comes focus in meditation, than force and pressure!