There is a comic very cool, called “ Sabre”, is a bit of this style. I recommended is very very cool. Sabre - comic amazon
Look up "Wall/canvas texture" on google, save it and import the texture in your drawing/editing app, and play around with blending modes ("multiply" and "soft light" would work the best for stuff like this).
Some apps have built-in textures, so you might wanna check the effects panel if your app has one.
I hope that you're being safe with bloodborne pathogens and cross-contamination. There are several diseases you can get/transfer of you don't know what you're doing; hiv/aids, hepatitis B and C, mrsa etc. I tell you this because you seem to have a good attitude and took my brash criticism well. I would suggest getting a legitimate apprenticeship, go to a reputable school or read this if you're going to continue tattooing https://smile.amazon.com/dp/1734185201/ref=cm_sw_r_cp_apa_glt_fabc_54T9D3A6YVHTWNMGS7A6
Your work was not horrible. Don't kill anybody.