Which type of sentence is
Rohan always walks to school ,but is never late for his lessons

I think it'll present continuous tense

Explanation:

This book is prefaced by the novel The Pilgrim's Progress that is a symbol of how to live as a Christian. In this preface it is included the females character of the book, MERCY, no its male character, so it is a sign that this book is a guide for young girls, it is a guide to get the salvation and the self-improvement.

Alcott wants to emphasize that religion is more important that everyday details of life. The four March sisters have to follow saintly feet and have a spiritual journey through their lives, in spite their situation as  "little tripping maids".

"Tell them of Mercy; she is one

Who early hath her pilgrimage begun.

Yea, let young damsels learn of her to prize

The world which is to come, and so be wise;

For little tripping maids may follow God

Along the ways which saintly feet have trod."