can they modify acoustic guitar to semi acoustic guitar ????

Answer 1

Yes, this is possible. What you need to get is a pickup which can be attached to your existing acoustic guitar. They can either be attached directly in the sound hole, underneath the strings, or else you can get ones that are inserted underneath the bridge, which has less effect on the natural acoustic sound but which requires a bit more work to install (and you may have to get someone professional to do it).

There are various different brands, and price ranges, with the more you pay generally the richer the tone. There's a page listed below that has done a good comparison of a whole range of options, and another with some images. Most guitar shops will stock at least a few options, and should let you try out the sound hole ones if you take your guitar in.

Answer 2

SEMI YES