Renewing a tenancy with Tenancy Builder is easy by following these steps:

Navigate to Tenancy Builder and click Tenancies in the sidebar.
Locate the tenancy you wish to renew.
Click on the action button on the left and select Duplicate. The newly duplicated tenancy will appear at the top of the tenancies list.
Via the action button, click Edit to edit the duplicated tenancy.
Change the dates on Page 1 as necessary, and if a new rent has been agreed, change that too. You should update the gas safety record if it has changed since the previous tenancy; otherwise, all other fields will probably remain unchanged.
On the last page, select Save and Build to generate a PDF renewal.
Optionally, send the renewal for digital signing via the action button.

A few notes about renewals:

Generally, the Guild does not recommend renewals. Instead, the tenancy can be left to roll on as a periodic contract. The rent can be increased every 12 months. That said, if all parties agree and wish to renew, that is fine too.
For England, renewals will mostly become obsolete when fixed terms are banned and most tenancies become periodic.
Technically, the documents you uploaded (EPC, gas safety record, and electrical inspection report) are not necessary for a renewal, as long as the tenant already has the latest versions. However, we recommend attaching the latest versions nevertheless.
A renewal is defined as a new tenancy between the same landlord, property, and tenants. If there is any change (for example, a different composition of tenants), it is technically not a renewal but a brand new tenancy. However, the duplicate method described above can still be used if preferred.
Duplicating the agreement is better than editing because if you edit an old tenancy, the edits will overwrite the earlier data and it will be lost. If digital signing was initiated, the edit function is not available, so duplicating is the only option, then edit the duplicate.

Renew Your Tenancy Easily with Tenancy Builder