tweek the twitter block

Dear all, I've embedded my personal twitter handle in my site. Unfortunately there is no option to change the font or size of the text of my feed. Also my retweets appear differently. they do not show any included link embedded but instead as "... https://t.co/...." link in the text. is there a chance or workaround to have the feed look like as on twitter.com or the twitter app? i mean, with embedded pics, links, retweets, etc...I also read about being able to set the font size anywhere in CSS - but actually I do not know where. Any ideas for me? Thank you in advance, best regards, Christian