The researcher needs class. For example 10 - 14, 15 - 19, 20 -24 ....... with frequency 2,5, 7....... then the lower limits will be 10, 15, 19 ....... and upper limits will be 14, 19, 24 ...

thanks

I don't understand what you're asking. Likert scaled items usually do not need limits. They give the limits. If you want to know if there is a preferred way to transfer interval data into categories it depends. Usually I can be done in several ways and only sometimes it makes sense to prefer one scheme above another. Sometimes Likert scaled items do have upper and lower limits, so called anchors. 'Always'  and 'Never'  are anchors, because there can not be values outside of these answering categories. 'Strongly (dis)agree'  are not. Then it needs to be ' Absolutely (dis)agree'. Even with these it is not 100% sure if these are anchors.

it is preferred not only to take the extreme  readings in likert scale, but if you have 5 points and you want to do dichotomy readings, then you can take the 4 & 5 together and 1,2, & 3 together