My bottom front tooth is trying to kinda overlap the other, but I do not want braces. Would a retainer fix this?(photo)

Your dental arches seem slightly narrow. If you have braces, not only your teeth be in better position, but your smile will also appear wider/fuller.

If it is just starting to overlap as you said,  a removable appliance such as an active retainer or clear plastic aligner can be very helpful.  You just need to be very committed to wearing it full time - for at least a few months. A visit to an orthodontist will confirm this and make sure no other issues exist. An appliance will also need to be adjusted periodically and progress monitored.