You could try and see if this code works for you. Adjust the height and width as required.
import streamlit as st
import base64
def ViewPDF(wch_fl):
with open(wch_fl,"rb") as pdf_file:
base64_pdf = base64.b64encode(pdf_file.read()).decode('utf-8')
pdf_display = f'<embed src="data:application/pdf;base64,{base64_pdf}" width="1000" height="500" type="application/pdf">'
st.markdown(pdf_display, unsafe_allow_html=True)
ViewPDF("./tst.pdf") # provide file path + full file name