How can I re-design with fewer tables? - sql

Question

I have designed a database for online donation. I have not added foreign key relationships because first I want to achieve a simple design. It's currently 11 tables, and it seems already more complicated than necessary.
The first one is registration table. The other 8 are different item types which will be donated by donors or by receivers, and 1 will be for post table it means when the user or receiver wants donate they will post what they want to donate or what they want ask others to give them. The last one will be for comment, the comment might be on the post by donors or receivers.
Can any one can help me re-design this in a simpler way?
Create Table Registration
(
ID int NOT NULL primary key,
FirstName varchar(25) NOT NULL,
LastName varchar(25) NOT NULL,
Username varchar(20),
Gender varchar(10),
Home_Address varchar(100),
Office_Address varchar(100),
City varchar(25),
State varchar(25),
Zip varchar(25),
Contact_No int ,
Email varchar(25)
);
2 posts
CREATE TABLE Post
( p_id int constraint p_pk primary key,
Username varchar(25),
Status varchar(25),
image nvarchar(max),
date_time varchar(100)
);
3,
CREATE TABLE Books
(
ISBN nvarchar(200) constraint ISBN_pk primary key,
Username varchar(25),
Book_title varchar(25),
Authorname varchar(25),
Publicationdate varchar(25),
Purchasedate varchar(25),
Book_edition varchar(25)
);
4,
CREATE TABLE images
(I_id int constraint i_pk primary key,
Username varchar(25),
Title varchar(25),
url varchar(50),
description varchar(100)
);
5,
CREATE TABLE laptop
(
L_id int constraint L_pk primary key,
Username varchar(25),
Model varchar(25),
Speed varchar(25),
Ram varchar(25),
HD varchar(50),
Screen varchar(50)
);
6, other items
CREATE TABLE other_items
(O_id int constraint O_pk primary key,
Username varchar(25),
Item_title varchar(25),
Item_type varchar(25),
Item_description varchar(100),
Itempicture varchar(100)
);
7, recipient
CREATE TABLE Recipient
(R_id int constraint R_pk primary key,
Firstname varchar(25),
Lastname varchar(25),
National_id_no varchar(50),
Address varchar(100),
Contact_no varchar(100)
);
8
CREATE TABLE Shoesimages
(
s_id int constraint Rss_pk primary key,
Username varchar(25), standard varchar(25),
Gender varchar(25),
Colour varchar(25),
Description varchar(100)
);
9,
CREATE TABLE uniform
(U_id int constraint u_pk primary key,
Username varchar(25),
Standard varchar(25),
Gender varchar(25),
Colour varchar(25),
Description varchar(100)
);
10,
CREATE TABLE Research_paper
(
Rs_id int constraint Rs_pk primary key,
Username varchar(25),
title varchar(25),
authorname varchar(25),
year_of_publish varchar(25),
venu varchar(100)
);
11,
CREATE TABLE Comments
(
C_id int constraint C_pk primary key,
Username varchar2(25),
comment nvarchar(max),
date_time varchar2(100)
);